Had protected sex with my girlfriend and she had an ipill within 72 hours. her period got delayed by 4 days as of now. anything to worry.?

Maybe: If you mean, by protected sex that u used a condom, remember that IRL a condom can fail up to 18% of the time. The iPill, if used on the last day (49-72 hours) is only 58% effective. To minimize the risk of pregnancy (and STDs) always wear a condom and discuss with your girlfriend about having a more dependable method of birth control (the pill, the patch, Depo, Implanon, etc.).