I took a rather circuitous route of playing and learning piano for 15 or so years (I'm 25 btw, I just started early) and being a massive theory nerd. I also taught myself piano until I got to college, which I think gave me unique perspective but I also know took waaay longer than it I'd just taken lessons. At the same time, I really enjoyed learning as a passion instead of a commitment. There were times I walked away but I always came back. That's just me though; if you learn better with the mild pressure of a teacher's tutting that's absolutely valid.

I've currently teaching myself as I just love exploring. I've watched some youtube videos about scales and I follow a few guitarists on youtube (samurai guitarist[0] comes to mind and Paul Davids[1] has probably been my biggest influence in my ability to play). Other than that, it's all been throwing all of my experience at it and seeing what sticks and what doesn't. Definitely record yourself once and a while to see what's working, and listen to a lot, both passively and actively, and try to spot what you like and really analyze it.

speaking of which, I've found music theory to be completely indispensable in my ability to self-study. Being able to take what I heard and internalize it, and being able to take what's in my head into my hands is absolutely essential.