6 days late and impatient

Hi everyone so I stopped my birth control (Lutera pills) in Feb. I took them for a year only. My last period was March 22 and had it for 3 days. (I have a 22 day cycle and had sex on the 26th) I haven't got my period yet and was suppose to have it last Thursday. I took a test in the morning when I woke up yesterday and it was negative..when I should I see a doctor? When should I take another test.