Weird

Krystal • Fri, Jun 12 • TTC since February 2014. Miscarriage at 7 weeks on Dec 4 2015, 2009 son, 2018 daughter

So I'm 8 days late for AF, today I've been crampy but only on one side. Usually when I get AF cramps it's all the way from one side to the other, and doesn't normally start until AF has already arrived. Anyone experience this or know what it could be? I have tested and got bfn.