Nausea..... BFN???

For the past few days I have been feeling on and off sick, like super nauseated. I took a test and it was bfn! Anyone else get a bfn then few days later ended up bfp??

*JustHoping*

Edit: I have not had a regular period last month or this month. So I have no idea when I ovulated. I did however spotted on and off...