I've been playing guitar 15 years and it has all been by ear and playing with other people, bands, etc. I'm feeling like I need to know stuff thats behind the ear in a technical sense but I don't know where to start and what I need and what I don't. Feeling kinda stagnate and need to find whats gonna take me higher. Any suggestions?

you mean like learning theory?

if you do try musictheory.net
Quote by Dirk Gently
Some pieces are only meant to be played by people with six fingers on their fretting hand. Sorry.