Unprotected sex

So..I'm on beyaz and have been taking it regularly..within 3 months I'd say I missed one pill but made up for it like I'm supposed to.. I have also been skipping periods. I skipped December and january(according to the pill pack anyway) about a week ago I started to get some breakthrough bleeding which I've read can be expected..

It slowly stopped over the weekend for the most part. Monday I ended up having sex and we also used spermicide. Now...if I didn't skip the placebo pills for january..my period would be due this week. Last night I had some cramps... went to the bathroom this morning and whipped some blood.

4 days is way too early for implantation bleeding..right?