Heat flashes lasting 3 hours

Last night I was outside and it wasn't even warm out and I was pouring sweat the entire 3 hours I was out there. SO said I felt warm then said I felt cold a little after but omg was I dying!! And dizzyness like crazy I could beaky stand at times. I was 7 days late with af then have had light bleeding for 3 days like super super light bleeding (today is third day) and the first day of spotting I had horrible cramps for about 2 hours then they were gone... took a test this morning and it came back ➖ I don't know if what happen with me last night is a sign of pregnancy or if I should go to the doctor ? I have been nauseas for the past few days even threw up this morning.