Cramps after BFP?

Hi ladies! A few days before I got my BFP I started having mild cramping. Which is weird for me as I never cramp before AF, only WITH AF. I got my BFP yesterday, still cramping. I had a temp dip today and freaked out running for a FRER. I took it and my line is MUCH darker than yesterday. The cramps just worry me. Are they normal? They are kind of like very mild AF cramps (mine with AF are usually pretty intense and these are just kind of a very dull version of them). Any insights would be so appreciated! I'm trying to just to accept that I am PG and nothing is going to happen but I've been worried since I told my husband.