i took cefuroxime and zithromax for a week last october for upper respiratory tract infection. on the 2nd day i had minimal menstrual for almost 5days. that was just almost 2 wks after my period for last mon (september). now its been almost 2 weks but i havnt had my real due date for october. its already november..im thinking if my cycle became irregular bec of that or is it just late or the flow when i was sick is already for oct.? :-(