Birth control and long period????

So I’ve just gotten on birth control and I’m in the 3rd week of using it. My period came early and so far it’s been lasting longer than usual. I thought it was finished today because of how light and pretty much non existent my flow was throughout my day but I just went into the bathroom (mind you it’s 11:17 PM when I did this) to see that there is a lot of blood coming out still on my cycle log I’m on day 10. Can someone explain if this is normal or not PLEASE?