Why do i have slight uterine discomfort? it's been going on for 7 days. i had unprotected sex on the 19th 14th and 17th. it's barely noticeable

Unclear question: If you miss your period by 4-5 days, do a home pregnancy test. If the result is negative repeat the test 4-5 days later unless you get a period by then. Use first morning urine and follow the instructions for the test carefully. If you do not wish to be pregnant, use contraception all the time, every time. You may consider implanted contraceptive, or IUD. Practice safe sex. Get HPV vaccine.