Period still going 11 days and counting

[springmachine]

I started my period 11 days ago.
It's still there now. It's light but I'm still cramping.

I have had the cool fitted for around 16 months and most periods have been 6 days long and very reliable.

Is there anything that could cause this?

It also started about a week earlier than normal too. It started on cd 26

I think you need to get medical advice, that doesn't sound normal.