Blood clots are a serious issue, as they can be life-threatening. According to the Centers for Disease Control and Prevention (CDC), an estimated 900,000 people in the United States are affected by this condition each year. The CDC further estimates that 60,000 to 100,000 people die from this condition annually.

When a blood clot occurs in one of your veins, it’s called a venous thromboembolism (VTE). If you’re even slightly concerned you might have one, call your doctor right away. Symptoms of blood clots can vary. It’s also possible to have a blood clot with no symptoms.

Read on to learn about some of the symptoms that may indicate a blood clot.

Blood clot in the leg

A blood clot that shows up in one of the major veins in your body is called deep vein thrombosis (DVT). They’re most common in the legs or the hip region. While the mere existence of a clot in your legs won’t harm you, the clot could break loose and lodge in your lungs. This leads to a serious and potentially fatal condition known as pulmonary embolism (PE).

Signs of a blood clot in your leg include:

These symptoms especially point to a blood clot when they occur in only one leg. That’s because you’re more likely to have a clot in one leg as opposed to in both legs. There are some other conditions and factors that could explain these symptoms, however.

To help distinguish a potential blood clot from other causes, Thomas Maldonado, MD, vascular surgeon and medical director of the Venous Thromboembolic Center at NYU Langone Medical Center, offered some more detailed thoughts on what someone might feel if they have a blood clot.

For one, the pain might remind you of a severe muscle cramp or charley horse. If your leg is swollen, elevating or icing the leg won’t reduce the swelling if it’s a blood clot. If icing or putting your feet up makes the swelling go down, you may have a muscle injury.

With a blood clot, your leg may also feel warm as the clot worsens. You may even notice a slight reddish or bluish hue to your skin.

You shouldn’t worry about a clot if the leg pain is made worse with exercise but relieved by rest. That’s most likely a result of poor blood flow through the arteries rather than DVT, said Maldonado.

Blood clot in the chest

Blood clots may be more common in the lower legs, but they can happen in other parts of your body, too. Where clots form and where they end up influence which symptoms you have and the consequences.

For example, when a blood clot forms in the arteries of the heart and blocks blood flow, it can cause a heart attack. Or a blood clot could travel to your lungs and cause a PE. Both can be life-threatening and have similar symptoms.

Chest pain is a sign that something is wrong, but figuring out if it’s a heart attack, a PE, or just indigestion can be difficult.

According to Maldonado, the chest pain that comes with a PE may feel like sharp pains that get worse with each breath. This pain may also come with:

A pain in your chest that feels more like an elephant is sitting on you may be a sign of a potential cardiac event, such as heart attack or angina. The pain that goes along with a potential heart attack may center on your chest. It might also radiate to the left part of your jaw, or your left shoulder and arm.

If you’re sweaty or have what feels like indigestion along with chest pain, that’s more cause for concern of a heart attack, said Patrick Vaccaro, MD, MBA, director of the Division of Vascular Diseases and Surgery at Ohio State University’s Wexner Medical Center.

Both conditions are serious, and both warrant further immediate medical attention.

Is your chest pain from congestion or wheezing? That’s more consistent with an infection or asthma, said Maldonado.

Blood clot in the abdomen

When a blood clot forms in one of the major veins that drain blood from your intestine, it’s called a mesenteric venous thrombosis. A blood clot here can stop blood circulation of the intestine and cause internal damage in that area. Catching a clot in the abdomen early may lead to a better outlook.

Some people are more at risk for this type of clot than others, said Caroline Sullivan, nurse practitioner and assistant professor at Columbia University School of Nursing. This includes anyone with a condition that causes swelling of the tissues surrounding the veins, such as:

Taking birth control pills and estrogen medications also increases your chances of having this type of clot.

The symptoms of a clot in the abdomen may include abdominal pain, bloating, and vomiting. If the stomach pain gets worse after eating or worse over time, it’s more likely to be associated with a clot, said Sullivan.

This pain might be severe and seem like it’s coming out of nowhere. It’s not something you’re likely to have experienced before, said Vaccaro, who compared it to “some of the worst pain an individual can experience.”

Blood clot in the brain

Blood clots that form either in the chambers of your heart or within the carotid arteries in your neck have the potential to travel to your brain. That can cause a stroke, explained Sullivan.

The signs of a stroke include:

Unlike most of the other signs of blood clots, Vaccaro noted that you likely won’t feel pain with a stroke. “But there may be a headache,” he said.

For more details of what having a blood clot might feel like, read some real stories of people who have experienced one at the National Blood Clot Alliance (NBCA).

When to call your doctor

See your doctor if you think there’s even a small chance you could have a blood clot.

“The sooner the blood clot is diagnosed, the sooner treatment can be started and [the] chance of permanent harm can be reduced,” said Vaccaro.