11dpo, dr. Appointment tomorrow to see what's going on

I've had nausea, slight cramping, back ache, pulling, pressure. It really started around 4-5 dpo, 6dpo it stepped up a bit, 9dpo I got extremely nauseous when I went to bed. Yesterday & today it's comes and goes. I never get nauseous before AF & I don't get cramps until 2-3 days before. Today 11dpo I took another test & it's was obviously negative so I can't help but get down again. Have a doctors appointment tomorrow to see if there's something more going on. I was so confident this was the month especially after the test the other day with a slight line. 😦😢

Has anyone had a negative then a positive?