Hi there. Normal range for period length is 3 to 7 days. So, you are within normal. I would consider this just to be an off month. good luck hon
Yes this is normal. Even though your period normally runs 4 days, it's not always going to be just 4 days. Remember that it can run up to 7 sometimes 8 days.
The non stop bleeding can simply be just you having a very heavy flow this month. Everything can make noticeable changes in your period. For instance eating habits, stress, or how much exercise you get.
A period that's different than what you normally have is okay. Don't stress about this. Wait a couple more days and see how everything is going. If you feel the need to take further action, like a trip to the gynecologist's to assure yourself, then so be it.
Stay positive!!
Good Luck!!