It's all in the stickies. I'm a newbie to this forum but not so in regards to health and fitness. If you ask obviously uniformed questions you will not be well received. I'm not trying to be rude. With all due respect, educate yourself by doing your reading. That process will inform you and it will generate meaningful questions that the community on here would be more than happy to answer. And again, you're too young to be interfering with your physiology. If you're hitting a wall just change your routine and/or get a trainer.
For testing, ask for a comprehensive metabolic panel, thyroid, testosterone, and complete blood count. It may be hard to get them to order more specific hormone tests unless you are symptomatic or any results in these listed tests are out of whack. Chances are they will all be normal only reinforcing the fact that you just need to put in some work at the gym and get scientific about your diet.