question: Hi, I was doing was push ups the other day and felt something click in the back side of my upper arm. It did not hurt at that moment. about a day and a half later I awoke with my arm being sore and now cant reach behind and inter lock my fingers as I was able to before. Also it hurts to put pressure on it as I try to push off the chair to get up. Is it more sounding like a pulled muscle or something more serious?