Can Antibiotics Cause Vaginal Infections?

I have been on amoxicillin for a sinus infection. Today was my last day. However, two days ago my urethra got irritated and today it seems like there is white discharge coming out of it. There is not any painful urination, but today I noticed when wiping that there was very light pink spotting coming from my vagina. It seems strange that I would get an infection while on antibiotics.