Ill guess I give my two cents(many things to get of my chest but i try keeping it brief)
Training and the effects on the human body are way more complex than you think.
Get fit to lift and not the other way around, work on mobility and other weak links. You will suffer other vise.
No matter what you do your body it will adapt, change things up. Great way in doing this is by following planned periodization try 3 weeks of pre-peak (5x5) ,than 3 weeks peak (3x3) and then 2 weeks of deload, prehab, let your body rest, you may try some less taxing bodybuilding like set and repetition ranges. (Just a quick summary this is a way more complex area)
Rest, you need rest, you cannot beat the shit out of your body continuously.
Injuries suck, treat them first don't ignore them.
This cant be summed up in a simple forum post, i actually wrote an article (hope my writing has improved) on a similar subject.
Athlete Mistakes RawGrip.com
I'm just scratching the surface, looking forward to many more replies.