How do you know if you have depression?

[Hd-x]

In addition, my testosterone levels, which have always been on the very high side have plummeted recently and are now abnormally low

T-levels may vary from time to time, the question still if yours T-leves are permanenty low?
, if so - it usually will have impact on the mood and a well balanced TRT could "perhaps" with some luck help more then any psychotropic drugs
A TRT it is mostly a life time decision, with all it goods and bad sides.