Conceiving After Depo ??

So last year in August I've Decided to get on the Depo shot after having my son .. I took the Depo 3 times & the last one I got was in Feburary . It was suppose to wear off by May . How ever now I'm trying to conceive a baby & it's really hard . I have sex with my boyfriend more than usual & still nothing . No period No spotting or nothing . Does anybody know how long it really my take to conceive after  getting off Depo ? I asked doctors & they said I could get pregnant right away but it's been 6 going on 7 months now .. Anyone been on Depo & got off & got pregnant ?