Redness/burning sensation. Medicines.

3-4yrs ago i had fallen flat on my chest one marble floor while swinging in the rod. At that time i didn't have any issue. But recently i have started having redness on the left side of my chest. When i try to stretch left ribs, i feel little pain inside as if some muscle is stuck and i m trying to pull it(if tried more cracking type of sound from ribs can be heard). However if i sit straight and keep my posture right, i m in much relief. But if i try too much to stretch my muscle redness occurs and can be seen with eyes near mammary area+little below. However during sleep i do not feel any pain as the muscle are in relaxed posture. After having a meal,some kind of burning sensation can be felt. I have done xrays and MRI but all the report says everything is normal. Am i suffering from anykind of allergy or what exactly is it. Please help me with some medicines.