Beware of doing strength-training of the same muscle group more than once a week (except for legs, up to a limit).
Also, sorry, but "Gallon of milk a day" is broscience.
Go to a non-fad sports doctor to get a good diet matching your training plan and goals (both micro and macrocycles). Lots of greens and healthy protein (i.e. not cow's except for whey protein powder). No sugars (including lactose), like ever. No refined food (unless you are into ultramarathon or similar). Time your foods.
A very common mistake is getting confused of what you should do while training and while competing. Yes, competing it makes sense to get as much carbs as possible to improve performance. But when training it's better to be starving and forcing your body to burn fat. Guys at the gym drinking Gatorade = losers. High glucose blocks growth hormone secretion!
http://www.pponline.co.uk/encyc/human-growth-hormone.html (nasty popup closed bottom right)
This guy advised some winning olympic british teams of 2012.
Also, we have a different genetic composition. Compare your gains to yourself. Else it's like getting depressed because you can't ball like the 7ft guys at the NBA.
This is completely false, if you're a beginner you can absolutely work the same muscle group within the same week and still get results. As you become a more advanced lifter, of course, this becomes less true.
>"Gallon of milk a day" is broscience
What do you mean? Are you saying that milk isn't a good choice if your goal is to get a high number of calories with a large proportion of them coming from protein? Calling this broscience just doesn't make sense.
Sounds like you have done your homework though. There's no harm in getting tested so I would talk to your doctor.
Before searching out testosterone I would try a beginners lifting program (meaning linear programming, where your lifts go up every workout) and eating a lot (3000-4000kCal a day). Starting Strength (my recommendation), Stronglifts and Ice Cream Fitness (ICF) are 3 popular ones.