First pap smear

Hello everyone I'm 21 years old I'm getting from first pap smear is there any advice y'all can give me I'm little nervous also quick question... my appointment is this Thursday and I just started my period today by then I'll be on my last day/second to last day of my period do I have to reschedule??? I've also heard it's best to have papsmear after your period how true is that???...