My calf is hard and sore in back due to swelling. cause for concern? i thought i had a muscle spasm that wouldn't go away until further inspection. most of the skin of my calf is tight due to swelling which caused the pain and is very hard. my ankle has s

Have : Have this checked immediately you could have a clot in your leg that can dislodge and go to your lungs. Don't delay.

R/o DVT & P.E.: When your calf feels hard & sore due to swelling, u need to check if it also warm and/or purple or red. If yes, should be suspicious for DVT and need to go to the E.R. Or your doctor's office asap, so he/she can order the appropriate tests (u/s of the leg, d-dimer) and get you treated. Other causes to r/o are hematoma/ compartment syndrome, tumors (i.e. Baker's cyst), aneurysm or cellulitis.