Oh btw..check rom on the shoulders. If you see a big difference between one and the other that will point to a need for some specific stretching. Reach behind your neck and try to touch the opposite scapula. On both sides. The idea is you should be able to do that. If one is much less rom than the other there you go.
Then reach around behind your lower back and try to touch the oppostie scapula. Same deal.
If you see discrepencies or rom just sucks than some gentle exernal rotator and internal rotator stretches may be in order.
Plus stretching the pecs and lats is strething the large internal rotators and they often get tight and over powerful compared to the small external rotators.
I'll put in a bunch of links later to help.
P.S. it doesn't really look like you are doing the mobility warmups and they may fix a lot of problems both present ones and potential ones. So if you're not doing that which has been recommended by me and others, and then you get pain, I gotta say...it'd be much easier if you'd do it
