Left collar bone pain?

I've been getting sharp pains near my left collar bone area the past several nights when I lay down in bed. It always freaks me out because I associate left shoulder pain with a leak, but I'm 6 months+ out so I'm hoping a leak wouldn't be a concern now, but does anyone know what this might be?

I used to have collar pain when I laid on my (left) side for too long.  I went to a PT for help and felt pretty foolish when she told me is was that simple.  

Are you lifting weights? If so it might be what they call weight lifters shoulder. It usually occurs at the end of your collar bone near your arm.