am I pregnant

Britney

hey guys so I switched birth control, I knew it was gonna mess with my period but I had some bleeding in the middle of last month I stopped taking it due to bad headaches. now I have missed my whole period this month I'm kinda concerned I took 3 tests & they are negative what do you think am I pregnant or is my period gonna be weeks late due to birth control!? or...should I keep taking tests??