Cramping?

So I’ve been cramping for over a week, no period, I’m 10 months postpartum so haven’t had one due to breastfeeding. Baby is sleeping at night so thought I could have been pregnant but all tests say no(not using bc) just curious if anyone else has gone through this before because this is new for me. I have also needed to pee a lot more and my nipples are extremely sensitive and I’m bloating a lot. Which I thought either meant my period would show or that I was pregnant. But nothing. Also a week ago when all of this started I was nauseous even threw up. And that’s why I took a test but again I took two and both were very clearly negative.