Due to intercourse on 1st and 2nd june, i had a UTI and was prescribed 5 TMP tablets before a week of my periods and haven t got my periods yet, i got my last date on 12th may, and my next period was to start on 9th june, 28 day cycle. Will taking TMP antibiotic affect menstrual cycle? I have weakness and light headedness, and low temperature. Is there any chance of pregnancy? please advise.