I saw another thread in which you quoted your chest measurement at ages 17-23 as 29". That suggests to me that either you were eating 300 cals a day
or your natural build is very light.
But even if you're naturally skinny, you can still achieve great results. I agree with Off-Road's middle paragraph above. My feeling is that one thing that may not work for you is trying to lose fat and build muscle simultaneously. You're probably going to have to throw yourself into one or the other.
There's no way of determining your T levels without getting it tested (second-guessing using sex drive, beard growth etc won't get you anywhere), and I can't see any harm in finding out. If you do so, please let us know how it went.