C dif symptoms and conditions

I have been taking Macrobid for almost a week and have Extreme nausea also and the worse case of Diarehea I have ever had in my life, I have lost 8 Lbs in a week. I have had very little sleep because even at night I am waking up to use the restroom between 5-8 times. I have tried to talk to my Dr but all the responce I get is that its a normal side effect and after a few days the side effects will deminish. Urgh! frustrating!!