Many things can affect how your body responds to a symptom and what kind of care you may need. These include:

• Your age. Babies and older adults tend to get sicker quicker.
• Your overall health. If you have a condition such as diabetes, HIV, cancer, or heart disease, you may need to pay closer attention to certain symptoms and seek care sooner.
• Medicines you take. Certain medicines, herbal remedies, and supplements can cause symptoms or make them worse.
• Recent health events, such as surgery or injury. These kinds of events can cause symptoms afterwards or make them more serious.
• Your health habits and lifestyle, such as eating and exercise habits, smoking, alcohol or drug use, sexual history, and travel.

Pain in adults and older children

• Severe pain (8 to 10): The pain is so bad that you can’t stand it for more than a few hours, can’t sleep, and can’t do anything else except focus on the pain.
• Moderate pain (5 to 7): The pain is bad enough to disrupt your normal activities and your sleep, but you can tolerate it for hours or days. Moderate can also mean pain that comes and goes even if it’s severe when it’s there.
• Mild pain (1 to 4): You notice the pain, but it is not bad enough to disrupt your sleep or activities.

Pain in children under 3 years

It can be hard to tell how much pain a baby or toddler is in.

• Severe pain (8 to 10): The pain is so bad that the baby cannot sleep, cannot get comfortable, and cries constantly no matter what you do. The baby may kick, make fists, or grimace.
• Moderate pain (5 to 7): The baby is very fussy, clings to you a lot, and may have trouble sleeping but responds when you try to comfort him or her.
• Mild pain (1 to 4): The baby is a little fussy and clings to you a little but responds when you try to comfort him or her.

Symptoms of a heart attack may include:

• Chest pain or pressure, or a strange feeling in the chest.
• Sweating.
• Shortness of breath.
• Nausea or vomiting.
• Pain, pressure, or a strange feeling in the back, neck, jaw, or upper belly, or in one or both shoulders or arms.
• Lightheadedness or sudden weakness.
• A fast or irregular heartbeat.

The more of these symptoms you have, the more likely it is that you’re having a heart attack. Chest pain or pressure is the most common symptom, but some people, especially women, may not notice it as much as other symptoms. You may not have chest pain at all but instead have shortness of breath, nausea, or a strange feeling in your chest or other areas.

Shock is a life-threatening condition that may quickly occur after a sudden illness or injury.

Adults and older children often have several symptoms of shock. These include:

• Passing out (losing consciousness).
• Feeling very dizzy or lightheaded, like you may pass out.
• Feeling very weak or having trouble standing.
• Not feeling alert or able to think clearly. You may be confused, restless, fearful, or unable to respond to questions.

Shock is a life-threatening condition that may occur quickly after a sudden illness or injury.

Babies and young children often have several symptoms of shock. These include:

• Passing out (losing consciousness).
• Being very sleepy or hard to wake up.
• Not responding when being touched or talked to.
• Breathing much faster than usual.
• Acting confused. The child may not know where he or she is.

Severe trouble breathing means:

• You cannot talk at all.
• You have to work very hard to breathe.
• You feel like you can’t get enough air.
• You do not feel alert or cannot think clearly.

Moderate trouble breathing means:

• It’s hard to talk in full sentences.
• It’s hard to breathe with activity.

Mild trouble breathing means:

• You feel a little out of breath but can still talk.
• It’s becoming hard to breathe with activity.

Severe trouble breathing means:

• The child cannot eat or talk because he or she is breathing so hard.
• The child’s nostrils are flaring and the belly is moving in and out with every breath.
• The child seems to be tiring out.
• The child seems very sleepy or confused.

Moderate trouble breathing means:

• The child is breathing a lot faster than usual.
• The child has to take breaks from eating or talking to breathe.
• The nostrils flare or the belly moves in and out at times when the child breathes.

Mild trouble breathing means:

• The child is breathing a little faster than usual.
• The child seems a little out of breath but can still eat or talk.

With severe bleeding, any of these may be true:

• Blood is pumping from the wound.
• The bleeding does not stop or slow down with pressure.
• Blood is quickly soaking through bandage after bandage.

With moderate bleeding, any of these may be true:

• The bleeding slows or stops with pressure but starts again if you remove the pressure.
• The blood may soak through a few bandages, but it is not fast or out of control.

With mild bleeding, any of these may be true:

• The bleeding stops on its own or with pressure.
• The bleeding stops or slows to an ooze or trickle after 15 minutes of pressure. It may ooze or trickle for up to 45 minutes.

Neurological symptoms—which may be signs of a problem with the nervous system—can affect many body functions. Symptoms may include:

• Numbness, weakness, or lack of movement in your face, arm, or leg, especially on only one side of your body.
• Trouble seeing in one or both eyes.
• Trouble speaking.
• Confusion or trouble understanding simple statements.
• Problems with balance or coordination (for example, falling down or dropping things).
• Seizures.

Symptoms of infection may include:

• Increased pain, swelling, warmth, or redness in or around the area.
• Red streaks leading from the area.
• Pus draining from the area.
• A fever.

Urinary tract infections may occur in the bladder or kidneys. Symptoms may include:

• Pain or burning when you urinate.
• A frequent need to urinate without being able to pass much urine.
• Pain in the flank, which is either side of the back just below the rib cage and above the waist.
• Blood in the urine.
• Fever.

Symptoms of a pulmonary embolism may include:

• Sudden shortness of breath.
• Sudden, sharp chest pain that may get worse when you breathe deeply or cough.
• Coughing up blood or pink, foamy mucus.
• Fast heart rate.
• Severe anxiety.
• Fainting.

If you have pain when you are breathing, you may be at immediate risk for a pulmonary embolism if you also have:

• Pain deep in one leg for no clear reason. This can be a sign of a blood clot in the leg (deep vein thrombosis) that could travel to the lungs.
• A history of problems with blood clots, such as deep vein thrombosis or a previous pulmonary embolism.

Severe vomiting can mean that:

• You vomit more than 10 times in 24 hours.
• For at least 24 hours, you vomit every time you try to drink something.
• The vomit shoots out in large amounts and with great force.