It could also be something wrong with your lebrum tendon. I hurt mine years ago working out and it was a pain exactly like youre describing. I couldnt lift my arm past 90 degrees in front or to the side without significant tension pain. I eventually found out that i had torn my tendon. If it stays painful to do those movements for more than a few weeks, you should see a doctor about it. If it is torn, it will take a minor surgery to repair.