Yes they can. You just need to mention to them that it is a concern you have. They will do some blood work, and depending on how fast they are with it, you can have your results withen a few days, or up to a week or more sometimes.
Now, obviously I dont know you, so I cant say for sure, but at your age, odds are you prob dont have low test.
When you get a chance, I would like you to take a look at the workout section of this site so we can set you up with a new training regimen. Again, after we help you get it all set up (diet, cardio, workout), I want you to go back to the doctor, and based on the results of your physical, have your doctor look over the diet, and everything else to make sure it is going to be 'safe' for you to do.
We can help you out a lot, but we are by no means professionals in the medical field, and cannot replace the advice of your doctor. If he/she has an issue with something we want you to run, make sure to tell us.