I need help with some shoulder problems?!

I have had this shoulder problem for about 4 years now. I used to play volleyball and tennis but all of a sudden, whenever I tried to do overarm serves or spikes of any kind, my shoulder felt like it was going to pop out and on a couple occasions, while sleeping, it popped out for about 15 seconds and then popped back in.

I've been to the X-ray clinic and the doctor and both of them said there was nothing wrong with me and that I shouldn't be having a problem. However, I still can't spike and I have to majorly decrease the power of my serve in tennis to not allow it to pop out.

I've just joined a gym and I'm having problems with any exercises involving any shoulder activities over my head. The other day I tried to swat at the fire alarm to stop it ringing and my shoulder almost popped out then too.

Does anyone have any idea what may be wrong with me that the doc and x-ray mightn't have picked up.?Health Question & Answer

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