Can amoxcilllin the antibiotic delay your period?

if you're on birth control and you're taking amoxicillin and you have unprotected sex you can get pregnant, because amoxicillin and many other antibiotics can decrease the affectiveness of birth control by half. So if you are on birth control, and you are taking amoxicillin, and you had unprotected sex you could be pregnant. Otherwise you're period could just be late because you are getting over an illness or you're body is fighting an infection.