Am i really pregnant or is this birth control shot messing wit me?

ok so i came off the depo shot in February, i bled every month like getting my period then i had unprotected once or twice and my period stopped in July....i have been feeling tired, sick but not actually puked, i haven't gained any weight but my got bigger...if i am pregnant then this would be my 4th month but i don't feel different likewise and i did take a pregnancy test and it was positive but that was 2 months ago and still no movements either, should i still believe I'm pregnant?