Periods

Okay so my period was 'due' 3 days ago, however my cycle is normally 36 days long (which is today). My mother is stressing me out as it hasn't turned up when she thinks I'm due on, which doesn't help me. Every time I've had sex we used a condom and pull out, so I'm not too panicky that I'm pregnant. I've been feeling more crampy today, is my period on its way?