Aamir, are you putting weight on the injured leg/limping? That'll contribute to pains in the feet and lower legs because our body weight is off balance and when you are walking differently, even with crutches, it forces your body to compensate by using muscles in different ways, which stresses them and causes them to hurt. If it is higher up on your calf it could be related to your injury, as sometimes there is soft tissue and bone bruising. The MCL attaches to your lower leg and injury to the MCL can cause pain in that area as well. I only had a grade 1 MCL sprain and I had pain quite a ways down into my lower leg. Some of it was caused by a bone bruise, but some of it was also caused by not being able to distribute weight and walk normally. It went away after about a week. If you are putting weight on the injured leg and limping, it might help to keep weight off of it entirely.