Help!!!!

Since i first started my period (nearly 5 years ago) they have been about 8 days long. Every single day it was a very heavy flow and the cramps and soreness were unbelievable. I finally went to the doctor to see if i can get on the pill to help regulate it/ slow it down a bit and so she gave it to me. This is my first period since I’ve been on the pill and the first couple of days were really light and i had NO cramps or anything!! It was amazing. But on my 6th day i started to get cramps (not as bad as before but still) and my flow got a little heavier. I’m on my 10th day right now and its exactly how it used to be again. So I’m just really confused?? Is it being weird bc i just stared the pill? Should i go see my doctor?