What is wrong with my mom? She keeps rushing to the bathroom.

See doctor. The urge to urinate or defecate may be caused by medical conditions or by medications. For example, frequent urination can be a symptom of diabetes, but may also be a result of taking diuretics for high blood pressure. If this is a new or problematic symptom, your mom should see her doctor for evaluation or a dose adjustment.
Nonspecifiic. Can be anything from a urinary tract infection to poorly controlled diabetes. Dropped bladders over active bladdrs etc should be considered. Medications can do this as well. Need to get her to the doctor for an exam, blood and urine tests.