Hi. so 2 days ago i was supposed to get my period. I still haven't but my periods are very very irregular so I'm not too worried. But the thing is, i had protected sex on the 27th of may, then a couple days later i had a UTI infection and was given antibiotics for 10 days. Can antibiotics delay your period? I really can't be pregnant. I read that it can delay ovulation or ovulation may not even happen. Im not sure. help?