Congratulations! Sorry you aren't feeling so well. Oddly enough I got a sinus infection with both pregnancies early on... the only two I've ever had. I'll call the OB first, then probably see the GP. They put me on antibiotics for it, but the kind that were okay for pregnant people. Helped greatly. They also did suggest a sinus rinse first - tried to avoid the antibiotocs, but it didn't improve.
Good luck and enjoy the pregnancy - it will go FAST!