Hi. So, was this a new activity? Guessing not since you said that you were playing the semi professional level. But is this a new level for you? Were you at a tournament or something where you normally don't play that much? Muscle stiffness wouldn't be uncommon. But this is more than that? You should probably get it looked at if so. You could have a thing called a slap tear if the pain is deep. This is a tear in the ring of cartilage that is around your shoulder socket. It would reduce range of motion. rotator cuff injuries are obvious to get checked out. Have you tried ibuprofen to see if that helps?
Hello~I highly suggest that you see your GP or a doctor that specializes in sports medicine, as the other posters have written, you may have some sort of tear that needs attention.