Levaquin and birth control pills

I took a 10-day course of levaquin for a sinus infection starting 12/22/06 and ending 12/31/06. I am a 43-year old female, fairly healthy. I experienced the following side effects intermittently during that time: acid reflux, diarrhea, tremors in my hands, fast heart-beat and I had a period in the middle of my cycle (I take birth control pills). I am not sure if that last one is related to the levaquin, but it's never happened to me before. Has any other woman experienced that with this or another antibiotic? I've taken other antibiotics before and only experienced nausea when taking it on an empty stomach and occasionally a yeast infection.