Do I need to see a doctor?

In the past 30 days, I have had my period three times. Which is a total of three weeks, or 21 days, and my flow is quite heavy. Is this normal? It has been over a year since my first period. Could something be wrong with my system? I was wondering if this was hereditary, because my mother had to have a hysterectomy. She, after giving birth to me, had two miscarriages, and she had her period for almost the entire month. Will I have to get things removed too? I'm afraid for this, because I am still young. Her period has always been extremely painful, I however, haven't experienced much pain myself. Just cramps in my thighs, and is this normal? Every girl I've talked to doesn't know what I mean when I say I have cramps in my thighs during my period, not just below my stomach.