Moderate Cramping but still BFP?

I am 13DPIUI and I'm having mild/moderate cramps like I usually get before AF shows. My blood test is tomorrow morning but I'm afraid AF is coming and it's going to be negative. I'm feeling sad and discouraged. Anyone ever experience true cramping close to a blood test and still get a BFP? Previously I had mild fluttery cramping but now it feels more like AF is about to show. 😔