Can I still be pregnant?

Patient: I have been taking microgestin for 4 months now. The first month I took birth control I bled a couple of days prior to my placebo week. So I did not take a week off and began my next pack right away. After that I took the next 3 packs back to back due to vacations and other events by skipping placebo week. I have had some breakthrough bleeding every month. I just finished my 4th month, but I missed 1 pill this month, however I am not sure how or even when because I recall taking a pill every day. Now I am on my placebo week, but I am not bleeding. I only have 2 days left before I start my next pack. I already took a pregnancy test and it was negative. I have very very minor cramps and no other symptoms. I wanted to know if there is still a chance of me being pregnant or if I missed my period because I took the pills continuously without a break for so many months.

Symptoms: very minor cramps