hello.. i need your help im 24 yr old having irregular periods some time 28 day cycle but mostly 32 last month in april my periods was on 8th april and having 32 days cycle my period was ended in 5 days on 12th of april. on 2st of april me and bf havibg sex but he was ejuaculated inside me not even precum before discharge he pulls back. now my periods date due on 7th or 8th of may and still i didnt get my periods im having quite similar symptoms just before my periods arrive like nauses and backache some times but this tym i feel quite much nauses which i never feel before feeling tired all time. 

today i took penorit and gyneacosid tablets for my periods??????

am i pregnant or this is just my stress...... please help me out