Ttc after depo any advice

I tried conceiving for a year after getting off depo got so tired of trying i took a year to just focus on completing school but we have now been trying for two months again. Ive been of depo 2 1/2 years. Im regretting ever letting my mom put me on it im 22 I should be able to conceive not trying. My period is due today it hasnt showed up so as soon as i got home i rushed to test only to get the clearest negative. Im upset and i know my fiancé secretly is too i try to act like its not my fault but it is and i know it