Before i started throwing yesterday morning i had some popping in my shoulder. I threw and the first 10-15 throws hurt but then it popped and I had my normal range of motion with no pain. but its continuing to feel a little sore. I thera banded last night and I dont know if something is weak or what. It feels either on top of the deltoid or where the deltoid and pectoralis overlap
Go see a medical professional and have it assessed.
Just a wild guess. Maybe something is up with your Bursa?