Thanks to all of you for good advice. I guess, as I thought, the number one thing for me is to just basically eat more. Alot more.
Yes, my T-levels are in the 600 or so range if I remember correctly. Got pretty good libido, so I dont think theres anything wrong with my hormones (although I know libido is more complex than just hormones). I do seem to add most of my weight around my stomach area though, which I didnt when I was in my early 20s.