heavy bleeding,irregular cycle&spotting.

i am having some bleeding pro...  [More]   blems.my 1st born was a normal delivery.i was 22yrs old when i had him.the 2nd one was a breech one so i had her by ceasearean delivery.afterwards i had two abortions.now the problem is that i am having irregular periods which are in for longer days say for 10-13 days(my normal cycle was of 28 days&five days a month.i'm having spotting also in between the current irregular cycle.my doctor says that my uterus is slightly swollen but  normal.she says its not menopousal its just harmonal imbalance.what should i do? please help me.it can't be first signs of cancer,is it?