Hi I'm 21 And Up Until I Was 14 My

Hi I'm 21 and up until I was 14 my monthly cycle had been the same day each month since I was ten when I turned 15 I noticed I would either have a heavy one then no cycle for two months or light and get one the next month but as I have gotten older they are spread out more the longest it has been was seven months I went to my doctor and they said it was nothing to worry about and they would regulate. Is there anything I can do or is this going to be something my body works out on its own
Thanks
Zoe