Period late! almost a week

Please give me some advice, im not sure what to do as me and my boyfriend have been together for alomost two years and have been having sex together for about a year and a half. I was on the pill before i met him but had to come off the pill about this time last year as it made me ill! I cannot recall the exact date of my last period but i know i was on over christmas but not on new year eve or poss 28th Dec! We allways use condoms and these have never split or anything during sex but i still havent come on this month and im worried as tommorow is the 1st of Feb!
Please help as im worried im pregnant!