My ebay site was in the US and now it's on the Australia site. What happened?

[originalgraysidecottage]

I have always bought and sold on the US ebay and all of a sudden where my name is, it says: G'day Kathleen. What the heck happened to me? 

All of my money issues are shown in AU format, not USD. How do I change it?

Kat (Kathleen)