I started birth control almost three months ago and the first month I did not have a period and the second month it only lasted a day. This month my period came a week early. I was wondering if this was normal

It usually takes your body a bit to get used to birth control. Any time you start birth control or even just switch from one pill to another it's common for your cycle to be a little off. My doctors have always told me to give any new pill 3 months. Are you on the kind where you have the three active weeks and then the inactive week? I would continue taking it as directed for one more month and if your cycle has still not adjusted by the end of the next pack, definitely check in with your doctor. And of course if you're still concerned it won't hurt to check in with your doctor before then either.