I just started testosterone injections because my testosterone was pretty low and Iv been having really bad depression and anxiety for years how long till I notice the testosterone injection helping the depression and anxiety I just got my 2nd inject?

Psychiatrist. While being treated for testosterone deficiency you should also be treated for depression and chronic anxiety. It's a mistake to try to tough it out as constant depression and anxiety will result in physical symptoms as well. Improvement in testosterone will help, but get a referral to a psychiatrist. A combination of cognitive therapy and, at least, temporary medication will probably be recommen.