Everymonth I have a 28 day cycle this month my period came at 21days
I Had sex April 5 and a April 15 could I possible be pregnant

If you had sex you could be pregnant... so yes, it's possible you're pregnant.

Of course, your cycle could just be off and you may not really be pregnant. It really is hard for us to tell if you're pregnant or not because we can't see you. You will want to see if you miss your period next month and then maybe take a home pregnantcy test.

No, you can't be pregnant, there's no such thing. You could however be pregnant.

You had your period, so it's unlikely that you're pregnant. Wait and see what happens with your next period.