I tried a bunch of stuff to fix it myself. My next step is getting some sort of professional help. But I’ll only be able to do that in almost two months, so I’m looking for what to do in the meanwhile.

Is the pain like in the front of the shoulder?

I’d say so, but only on the left.

Maybe you need to work your back and rotator cuffs. Also stretch your pecs.

How can I do that?