Pain in right calf after sitting or laying down. when i stand it is very painful and causes me to limp. it goes away after about 5 mins. black male 39?

Muscle strain/spasm: This could be a simple muscle sprain or spasm that when it is shortened from being in a flexed position, needs to be stretched back out which is why it gets better after walking around. This may be your calf or hamstrings as they cross the knee and attach behind the calf. Stretch both. If you have any swelling in that one calf, with severe pain that gets worse and doesnt improve, consider er visit.