Hello, I have gone through your query and understood the concern. From the description of your symptoms, it appears as though you are experiencing an infection. Menstrual disturbances can happen with general, pelvic and local infections. Chances of pregnancy with failure of tubal ligation are very rare. Though, cases have been reported often when the time duration from the tubectomy has increased raising the possibility of a tubal reanastomosis upon healing etc. If you are suspicious of pregnancy, you can either get a HPT a week after the due date or go for the blood test. Please report to your health care provider for proper help. Take care.