flagyl & discharge

I've been taking metronidazole (flagyl) for 4 days for bv. yesterday i noticed some light brown discharge. there seems to be no odor and my symptoms are improving. Just wondering if this type of discharge is normal with this medication. i did just finish my menstrual cycle 2 days ago, but i dont usually have left over blood discharge. if anyone has any experience with bv and the oral form of metronidazole, id love to hear about any side effects!