I had sex 2 days before my period shoul happen, after 24 hours I had anti pregnancy pills I-pill, and my period date has elapsed by 4 days and still I'm not menstruating.am I pregnant? Please help me.

I see you
1. did not talk to the doctor about the pills
2. did not talk to the druggist about the pills
3. did not even read the warning information that came with the pills ?

The morning after pills are well known for effecting your cycle for the next month or two. So not having a cycle is a common side effect of the pill.
** but also sign of pregnancy, so you will not know for sure at that point.

The pill is not 100 percent effective, so yes you could be pregnant.