Withdrawal bleeding after the i-pill varies between cycles, so not bleeding every time doesn't mean anything went wrong, and this time's bleeding by itself isn't a cause for worry. Using the i-pill this often isn't meant for regular contraception though, since it's far less reliable than a proper method and tends to disrupt your cycle, which is likely what you're seeing now.
Next Steps
If your period doesn't arrive as expected within the next week, take a home
pregnancy test to be sure. Please talk to a gynaecologist about switching to a regular contraceptive method so you aren't relying on emergency pills repeatedly.