Can An Excessive Sevista Dosage Cause Any Serious Side Effects?

My mom was prescribed to have a tablet sevista as she had over bleeding.Due to miscommunication she had apparently had over dose of than prescribed. She had taken close to 24 tablets in a span of 14 days when she was supposed to have had 8 tablets in the same number of days. She had fever and constant headache towards the completion of the course.Please advise if there would be any serious side -effects due o this.The doctor has not given any proper response. She has asked my Mom to visit her after 15 days and to stop all medication as of now. This is worrying me a lot...Please help.