What would cause your vain next to your ankle sting and swell? my vein next to my ankle started stinging, and got so big i thought it would bust, the little veins around it also swelled, ever since that happened i have felt weak, and upset to my stomache,

The : The most important thing to rule-out based on your description, would be phlebitis, an inflamed clot in a vein. The veins at the ankle level are small, so it's unlikely you have a deep vein thrombosis, but you're also having systemic symptoms, which can be a significant finding. A deep vein thrombosis has the ability to send little (or big) clots up to your lungs, and can even be life-threatening. Symptoms of a pulmonary embolus (a clot in your lung sent up from a leg vein) are shortness of breath and chest pain. If you have either of these symptoms, even mildly, you must go to an er now, and get heparin, which will dissolve the clot. I hope this is not the case with you, but i'm very concerned.

Possible phlebitis: Apply hot warm compresses.