Protected sex for the 1st time in 2 yrs on feb20. i usually get my period @ end of mon.leading into next. condom was used no ejaculation why no period?

Missed period: Since your period is late and you've engaged in sex, granted protected w/condom, it's still a good idea to take home pregnancy test. Chances are that your missed period is due to stress, weight change, thyroid disorder or perhaps coincidental start of change of life if you're old enough. Check w/your Family Doc or GYN if test negative & you miss another period.