shoulder pain

hi all i injured my shoulder a year ago i was helping my dad carry a reclining chair down stairs... he went down backwards and i was trying to make sure the chair didnt fall on him so i was arm outstreched hold this chair and it was bloody heavy !! anyway after i kept getting really bad pain...along the top of my shoulder its not joint pain...i been to docs a few times to be told id strained it then it was tendinitis.and i was given ibuprofen, which didnt touch the pain......any way i just started exersising again and it hurts my shoulder, and even just raising my arm hurts my shoulder still, and sometimes its so bad i cant use it.id say the pain was 8/10 when it gets bad ..i was thinking maybe i tore my rotator cuff ? just wondering if anyone else has had this type of injury can shed any light as i think i need to go back up doctors