Single object mapping to multiple textures by accident

I’m a newcomer to Blender and I’m trying to unwrap a simple model.
The problem is it seems I have multiple textures associated with it when I want only one.
I’ve split the window to show an Edit Object View and a UV Image View.
When I select some faces, it shows one texture on the UV Image View, but when I select others, it shows a different texture.
In the Materials and Texture tabs on the right I only have one material.
When I export my model to Unity, it seems to be using one texture on some faces and another on some other faces.

I’ve tried hitting U and re-unwrapping all faces but when I select individual faces again it shows one of the two textures.

How can I find out what’s going on?
How can I make sure my model is only using a single texture?

Thanks!

Check UVmaps on ObjectData tab; delete selected map using ‘-’ sign next. Delete all UVmaps to get rid of remaining ‘sticky’ textures which sometimes make living hard ;).