Hi! My Boyfriend And I Had Sex About A Week

Hi! My boyfriend and I had sex about a week ago, I was unable to take my pill that night (by the way I'm on trisprintec).... So I took 2 the next day to catch up. I have been spotting ever since I took 2 in one day. I have stomach cramps every now and then but now it's more like a lighter period. I start my period this Sunday evening.... What is going on with me? This has never happened before. Please help.