Cramps

So I have been off my bc for a little over a month. My bf and I are TTC. For the past few weeks I have felt like I may be pregnant but I also think I haven't been off my bc long enough to get pregnant. My period hasnt come back yet but even before going on bc my period was very irregular. I've been cramping in my middle/lower stomach for a while now and don't know why. I used to sleep on my left side and stomach but now both of those positions are so uncomfortable. Ive also had to pee 1000 times a day and I'm not drinking enough to have to go that much. I took a pregnancy test on Monday and it was negative so does anyone have any idea why I've been cramping and needing to pee so bad?

PS: I've had other pregnancy symptoms too, those two are just the ones I'm most curious about.