Hey man, I 'm 31 and in pretty much the same boat as you. I just bought a guitar and started on GT a few days ago. I started at fundamentals 1 which is where it sounds like you should start also. It goes over how to fret chords and how to avoid muting the strings underneath.

My first time trying to learn A minor, I kept hitting the 2nd string with my middle finger and it was very frustrating. The thing that helped me the most was plucking each individual note of the chord and adjusting my fingers till they were not in the way. once I had that I would strum the whole chord. After about a day, my muscle memory was there and now I can do all the chords I learned in the first few lessons with no prob. It just takes some time and patience, you'll get it if you stick with it.

My fingers burned like a son of a gun too, but already they are doing much better holding the notes and not hurting so much. I've been playing 1-2 hours every day though so I think that has helped.

Good luck to you!