Me and my boyfriend had sex 4 days to prior to my normal period due date. I missed my period and I'm 8 days overdue now? Did 3 pregnancy tests so far, first 2 3 days after missing the period. And 3rd one after 8 days overdue. All of them were negative. Can I be pregnant? I don't feel any kind of pregnancy symptoms except period overdue

It's possible, but sex right before your period is one of the least likely times to become pregnant. It may be your period is just off. Give it another week and see what happens. Test again if necessary. If still negative, wait until next month as you may just be skipping a period.