Question: what happens when you have a blood clot?
Answer: A blood clot in a leg vein may cause pain, warmth and tenderness in the affected area. Deep vein thrombosis (DVT) occurs when a blood clot (thrombus) forms in one or more of the deep veins in your body, usually in your legs. Deep vein thrombosis can cause leg pain or swelling, but also can occur with no symptoms.