Advise needed

I had my lb in jan 2015 I got the implant put in jun/jul 2015, I had it removed jun 2016 and had the injection in straight away (when I didn't even want that) I haven't had any more injections because me and my partner are trying for a baby as I think it's time for another. so it's been over a year and the injection should be out of my system? some times I can have a period and then I can go without a period for a month or two.. my last period was 3 months ago and I feel sick get belly cramps got head aches that turn into migraines.. today I noticed my hips have got wider or bigger.. i have done 3 pregnancy test and they have come back negative. has anyone else had the trouble after being on the injection?