What are my chances of joining the US army after being diagnosed with depression as a minor?

To give some referance, I just turned 20 years old. When i was 15 my dog died, my girlfriend broke up with me, and my father lost his job and we got the news we had to move to a new state within the same week. At the time i was fairly sad about the situation, so my mother brought me to a psychologist or therapist (not sure which) and i was diagnosed with depression and given anti-depressants. I dont believe i should have ever been put on meds or diagnosed, and believe i was misdiagnosed. I took the meds for about a year before realizing they were doing more harm than good for me so i stopped taking them. I believe i was misdiagnosed with depression, and should not have been given meds. It has been about 3 years now since i have been on meds or seen a doctor about anything sadness/depression related, and I have been doing very well. What are the chances of me being let into the US army? Would it help for me to get a letter from a doctor saying I am mentally fit for military service? I am not really sure what to do as I was a minor and my mother kinda pushed me into getting meds and being diagnosed. I really hope my chances arent shot because of this situation.