Antibiotics while pregnant

Aly
Hi everyone, I'm 11 weeks pregnant and have been sick with a nasty cold for the past 3 weeks. It ended up turning into a sinus infection about 5 days ago. I went to the doctor's again today since the natural things like tea and salt water nose spray just weren't doing the trick, and she said that there's no way around it, I need to get on antibiotics, and prescribed me amoxicillin. 
Have any of you ever needed amoxicillin during pregnancy? I'm a little worried about taking it, but can't imagine that baby will be too happy if I keep feeling so miserable.