The best advice I can give you has already been given.

I just went thru this a couple of years ago with a shoulder injured at work. Everything was denied...everything...for the first 6 months. They finally took care of the problem but it took an attorney getting involved and the threat of much larger lawsuit.

I also hurt my back in the early 90s on a drill weekend with the Air Guard. I, too, thought it would just pass with time and get better. It didn't and it causes me constant pain now, 20-something years later. I'm trying to work up the nerve to see a VA benefits advisor.