I'm 16 and haven't had my period in 3 1/2 months and just recently ( 5 months ago) came off Depo. I took three home pregnancy tests, all negative. I went to the health department and they said I was negative also. Everyone in my family and boyfriends family already thinks I am... They keep wanting me to go to the doctor, but I'm too afraid to because I think the test there will too be negative. My breast are leaking and I haven't had my period and I don't know what to do. I want to be... kinda... but I also don't want to let anyone down. Could I be pregnant?

It can take upwards of TWO years for your cycle to recover after the depo shot.
If you are concerned then you must see your own medical practitioner.