I am a very active person and sometimes whilst exercising I get cramps, as with most people. However, just over a week ago, I started to get cramps whilst lying in bed. Since then, I have had cramps (always in my left calf) very often (1-3 times an hour). Whenever I contract the muscle (by pointing my toes) the muscle spasms, but sometimes it happens when I'm just walking or even resting. It is very painful and is causing the muscle to contract to much that it is working it too hard. My left calf is now very hard, particularly in comparison to my right (despite the fact that I'm right-footed). It really hurts and is either massively swollen or the muscle has grown rapidly!
What should I do? Why is this happening?