Help..?

Ok so as of today I’m 12 days late. AF was due March 11th and I’ve had some mild and severe stomach cramps but mostly mild and durable. No signs of my period even starting. My blood pressure has just recently started rising for no apparent reason and I’ve been having really weird cravings.. dizzy and light headed but all the test that I have taken have been negative.. I don’t get why because I have never been this late on my period 5 days at the most but not this long.. I had a miscarriage the weekend of my birthday back in September.. I seriously don’t know what to do or what to think.. please help?!?