Advice please!!!

Hannah

Hi all. so I was on cerazette for 9 years, stopped taking it 2 months ago, had one period on 26/11/17 and nothing since. according to the app I'm now 9 days late. I have tender boobies, heartburn, nausea and slight menstrual cramps now and again. I took a first response test on Monday (at 5 days late) and it was negative. could I be pregnant this soon? Any advice as to what I should do? TIA :)