Heavier periods after Plan B?

I took Plan B after an incident on October 30. I’ve had two periods since then, currently on my second one. Both have been heavier than usual. My periods are fairly heavy anyway the first few days, but it seems to be heavy almost the whole week now. Is that normal? I don’t think I’d be pregnant since I’ve been bleeding pretty steadily/heavy and haven’t had any symptoms but still stress lol.