A blood clot in a leg vein can sit like a plug or break off and travel. Early signs are easy to brush off as a muscle pull, so knowing the pattern matters. Calf pain is the first red flag. It feels like a deep cramp or tight muscle that doesn’t ease with stretching or massage. Swelling shows up next. The ankle or whole lower leg puffs, often only on one side, so socks leave a tight groove. Warmth and redness appear. The skin over the vein feels hot and looks pink or purplish, like a localized sunburn. Heaviness and... Learn more