Missed my period despite being on the pill

Patient: I started taking my new pill packet last Friday and still have not had my period. Sensitive nipples for about 4 weeks, cramps last week and mood swings. Over the last month I took paracetamol with codeine, tylenol pm, domperidon, imigran and something for heartburn. Could this have affected my cycle? Two pregnancy tests taken on saturday and sunday were negative.