Ingenua, I wouldn't know from 'normal' and 'regular'. I started at 12 and right off the bat it was heavy and irregular. I lost a lot of time from school due to that mess. My mother finally took my to gyn and I was put on BC pills to help regulate it. I had been having long periods 2x a month. The pills helped to limit the time but not the flow. I have had FMS all my life, so this was my story forever. It got worse after my second son was born and I had tubal ligation. I had such a bad time that I finally had a hysterectomy 5 yrs. ago. I have heard that FMS can cause it to be worse. Since I've always had FMS, I have never known a different way. Sorry that's the best I can tell from personal experience.
God bless. Alice.