Hi Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concern... Yes menstrual cycles can become irregular post intake of emergency contraceptive pills like i-pill. This is due to high dose of levogestrol hormone contained in an emergency contraceptive pill. But this irregularity happens for 1 or 2 cycles only. So most common cause of menstrual irregularity in you should be the emergency pill intake. If the period you had on 8 Nov was heavy & had bleeding just like a normal period then you need not to worry, your periods will become normal with time. If bleeding was light & lasted for just 1-2 days then you need to be much concerned. Use condom or regular contraceptive pill as method of conception in future. Taking more emergency contraceptive pills can cause serious problems like irregular periods, ovarian hyper-stimulation syndrome, ectopic pregnancy & even infertility. If problem persists consult a gynaecologist Hope this information helps