Tommy, that is awesome you picked up mando. That’s great you have already learned two tunes. I love wildwood flower. I sometimes play that song over and over. I have someone starting on guitar in my group that is about your age. He started two weeks ago and seems to really enjoy it. Learning an instrument takes some time to get over the initial hump for everybody who I have ever seen do it.
Don’t worry too much that there is so much to “learn.” My suggestion is that if some part of it starts becoming work, just ease up and make sure to focus some on playing the stuff you enjoy as well. That’s why we play is to enjoy it. As far as the theory behind the scales and all that, people generally don’t get it right off the bat. It takes being around it for a bit and it kind of sinks in. Try to gain a little familiarity with it each week as you go along playing what you like. After a while, you can start to see how the theory fits into the songs you are learning and it is really neat.