Ask her to do a quick wash of surfaces, chances are you'll be just fine. I had a little cold when I had my c-section and they said as long as I wasn't down and out sick, I was fine to do it, actually my doctor said since I breastfed and having a minor cold (minor, very minor) she'd get the antibodies my body was producing to fight off the cold when she was very first born and that that was a good thing. I wouldn't worry about it, just don't let her breathe in your face and make sure you wash your hands often, you'll be fine.
What about the germs in her house like on doorknobs and stuff?
If she has been on antibiotics for 24 hours then she is no longer contagious and it will be safe to go over there.