i woke up Sunday morning and i could barely walk.i was limping cause i had this horrible ache on the back of my right knee.i don’t have arthritis or anything,im only 15 yrs old.what can i do to relieve the pain ? thanks

The muscles behind my left shoulder blade ache and burn and sore to the touch. I get relief when I can afford a massage. Is there a medicine or therapy I can do to stop the pain. I was told that it is a chronic condition.