PCOS and Metformin

Hello! I've been placed on 500mg of Metformin, once a day, and have been on it for the last 4 months. I've been having what I think are side affects of the drug but I'm not sure. Has anyone had crazy bowel movements (normal one day, constipated the next, followed by a day of diarrhea)? Also bad indigestion ? The crazy bowel movement started with day one of Metformin but the indigestion started here in the last month...I've tried everything to get rid of it but it won't go away. Anyone else have these issues? I'm not sure if it's all from the Metformin or something else......