Difficulties diagnosing injuries of the shoulder

It must be difficult to diagnose shoulder injuries. At first I was diagnosed with having rotary cuff tendinitis. Then, after a more in-depth evaluation, the verdict was deltoid tendinitis, a less severe injury than those associated with the rotary cuff. Now, after yet another evaluation, my therapist says that the deltoid tendinitis judgment was mistaken. It's rotary cuff. Whatever it is, I have to say that it's feeling better today, after two weeks of treatment and laying off the weights.