Femara fail or.....?

My doctor started me on femara without a bleed because I'm anovulatory and just came off of a thirty day period, I know wow. But I think this round of femara failed because about three days after taking it I started spotting on 11/9 and having clots every other day. So Right now on 11/15 I am still spotting and I only see blood after i wipe that's it. Has this ever happen to anyone else cause I'm scared im out for this month. I've been taking opks everyday and i know i had a postive on 11/11 and 11/12. I called my Dr. And got his nurse who says it could be normal.