I'm 23 weeks pregnant & last night woke up w/ the back of my left calf aching & w/ a burning sensation. my leg has been aching all day. whts going on?

Needs evaluation: The most likely causes is a leg cramp. Muscle cramps in the calf are very common if not almost universal. But these are also the symptoms of a blood clot (dvt). Dvts are more common in pregnancy and give similar symptoms. This is a serious condition. Although a simple cramp is more likely since your pain is continuing you should be evaluated promptly to confirm that you do not have a dvt.

Leg pain: Leg cramps at night are fairly common during pregnancy however pain in a calf with a burning sensation could also be the beginning signs of a blood clot. If it is a blood clot, that is serious. Therefore you should contact your OB right away to be examined and see if it is concerning or not.

DVT!!!: Please proceed to the emergency room now - I am concerned you may have a deep vein thrombosis that can even prove lethal in pregnancy! waste no time before you get properly evaluated at the emergency room!