What Causes Pain And Popping Noise While Rotating Arm?

Hi so I think I may have torn my rotator cuff but I dont know for sure. It all started last Summer during football camp when I made a tackle on a guy with only my right shoulder. Ever since then its always hurt when I ever I rotate the arm. I went to the doctor at the end of the season and he prescribed a shoulder stabilizer physical thearapy program. But still I see/feel no changes in my shoulder. It doesnt hurt all the time but whenever I try and block a shot in basketball, throw a ball, or just rotate my arm it hurts. Plus there is a popping noise whenever I rotate my arm. I went to the doctor a couple days ago and got an MRI but were still waiting on the results. But based on the symptoms what do you think it is?