Low testosterone, slightly high TSH - began testosterone therapy (labs included)

I'm 23 years old and have had a suspicion of low testosterone for a couple of years, due to little facial hair and low sex drive.  I had a blood workup for the first time and the following was found:

Testosterone, total  -  253 ng/dL  -  (250 - 1100)
Testosterone, free  -  46.7 pg/mL  -  (46 - 224)
Testosterone, bioavailable  -  108.3  -  (110 - 575)
SHBG  -  18 nmol/L  -  (7 - 49)
Albumin, serum  -  5.1 g/dL  -  (3.6 - 5.1)
LH  -  5.6 mIU/mL  -  (1.5 - 9.3)
FSH  -  5.3 mIU/mL  -  (1.6 - 8.0)
TSH  -  3.38 uIU/mL  -  (0.4 - 4.50)  (although I have read the AACE states above 3.0 should be examined)
T-4 (thyroxine), free  -  1.1 ng/dL  -  (0.8 - 1.8)

After receiving these tests at the student health center at my college, I am now on my first day with Androderm 5mg therapy.  I can be referred to an endocrinologist or an urologist by my physician whenever I would like to, if this is necessary.  Based on my low testosterone levels, but normal LH/FSH, he is diagnosing me with "idiopathic hypogonadism."  He also does not think that my TSH is worth examining any further, especially since my T-4 is normal, but said it's worth watching for any changes.

So, am I on track for the treatment of my newly diagnosed low testosterone?  Is 5 mg Androderm a good option for now?  Should I be referred to an endocrinologist to further examine and treat the testosterone, and possibly thyroid?

One concern I have about the testosterone therapy, especially at my younger age of 23, is the possible infertility with long term use.  I have read online it can be beneficial to use testosterone injections instead, along with a weekly hCG injection to prevent testicular atrophy, and even saw a recommendation for an aromatase inhibitor such as Arimidex to prevent the conversion of testosterone to estradiol.  Is all of this necessary, and I should speak with an endocrinologist about it?

Thank for you any and all advice and suggestions about any of the above questions :)  I am new to this world of hormones, and am a little overwhelmed now that it's confirmed that "something is wrong with me."