Even if i close my eyes i can say when i tilt my head. why is that?

The fluid in my ear is responsible for balance detection

✡ You can feel your mussels expanding and moving ✡

- - Reason for:

When you close your eyes, you cant see anything, but you can feel stuff.
If you closed your eyes and someone touched your arm... you can feel that.

You know when you tilt your head because you can feel the mussels moving and you would have to use your mussels when you do so. 

✡Hope this helps✡