I got off the depo in the second week of march and I still haven't had my period yet, my fiancé and I have been making love everyday since the third week of January, I started having a lot of syptoms of pregnancy the last three-four weeks and have taken one test, it came out negative could I still be pregnant?

Yes, but that's just 'could be pregnant.' We have no way of knowing if you are (no one does), or are just experiencing hormonal changes. Take another test and follow the instructions exactly.