Hot. All. Day. Anyone experience this?

Ladies, what are your experiences with feeling hot, nauseous, dizzy BEFORE your BFP? Up until now, I've had symptoms that could be all in my head but today it's definitely not in my head. I am 12 DPO and have been on fire all day, took my temp and no fever. I've also felt lightheaded, mentally foggy (I was driving to a friend's house and went the completely wrong way???) off and on sick, crampy, and generally very odd all day long. I can't think of any reason I'd be feeling like this other than getting sick, maybe? (Which would be a cruel trick this close to AF!)  Anyone else experience this? I'm trying to hold out until 14 DPO to test assuming no AF.