Tri sprintec spotting and cramps.

Patient: Hi, I started taking tri sprintec birth control on February 16th of this year. Instead of starting to take the placebo pills on Sunday, March 9th, I skipped the placebo pills and straight to taking the second pack in order to skip my period. Every day of the week of March 8th-16th I had unprotected sex using the withdrawal method. I am on time with all my pills, every day, besides missing one the first week and taking it in the morning the next day. My placebo pills begin this upcoming week, and from Thursday night until Friday night I had some spotting, of a dark brownish color for the most part and some slight cramps. I took a pregnancy test Thursday night which was negative. Could I still be pregnant, or is it a side effect of skipping the placebos or just my body getting used to birth control pills? Thank you very much for your help.

Symptoms: Spotting, slight cramps.

Doctor: