Had mine checked last April. It was on the very low end of the normal range. I was having depression, irritability, anger, etc. Libido was off a little too. Couldn't lose fat or put on muscle. I went to a urologist and got a prescription. My depression symptoms lifted within a couple of days. Get it checked.
This has been more my issues, was blaming it on a lot of other things before thinking, "This isn't me". Starting with blood test this week, and perhaps moving on to the saliva test next...