As has been mentioned on other threads, music theory is a definition of what we do when we play music - understanding what works and what doesn't is what you're after - which music theory helps to explain, but cannot in itself give you.
Getting a teacher is certainly a good idea, as it allows you ask questions, and (hopefully) things can be explained to you in a way that makes sense.
An understanding of theory, along with its practical application (something you can begin to use to dissect songs you're currently playing) will give you more options and more places on the neck to play, but don't forget that sometimes breaking "the rules" can sound good too