Is It To Be Concerned About A Sinus Infection During Pregnancy?

I am 6 months pregnant, 30 years old, and 161 pounds. I had a really bad cold and nasal congestion for two weeks that wasn t getting better. Then three days ago my sinus cavities, nose, upper and lower teeth began throbbing and aching. I called my ob and explained my symptoms. She said it sounded like a sinus infection and called me in a 6 pill zpac. I took the fourth pill today and still basically feel the same. I can deal with the sinus pressure but the aching teeth are killing me. I am also worried about the fever. Have had it for three days. It averages around 99.5. My normal temp is usually 97. Something. I wouldn t be worried if I wasn t pregnant. I know Tylenol is ok during pregnancy but only in moderation and I don t want to overdue taking it for the fever and pain. Should I be better now? Should the zpac be helping? Should I go to the er? Please help? I m scared for my baby and in pain