What’s going on?

Please help a girl out! I’ve been on the pill for years and take continuously until I start spotting and then I take placebo pills for a full week. Last time I got my period I only took 4 placebo pills and began active pills. I stopped bleeding for about 2 weeks and I have not missed since but I have been breakthrough bleeding a little bit everyday for over a week now. I also have a sinus infection and I’m unsure what to do. Could I be pregnant? It’s also very dark and brown. Help!