6weeks bad cramps and brown spotting

I'm 6+2 and have been cramping since probs 5+5. Last couple of days I've had light brown spotting in my CM, only enough to barely see on toilet paper. But the cramps are real! I don't usually cramp this much during my period for more than a day, where as this has been getting worse for the last 3 days. It happened before AF was due - before my BPF, and I thought AF was coming, but obvs didn't. Now it's happening again. Also from about 5weeks I've been getting really bad headaches and migraines.

Any similar advice/outcomes?