Texture from last object still there in UV Edit mode

Hi, I’m following a tutorial. Blender Foundations book.

I put texture on my floor, unwrapped my table, only to find in the UV Edit View that the carpet texture is till there.

Was there some ‘save’ function I should have done after finishing the floor?

Can I just remove the carpet texture now, or will that undo floor texturing?

If I remove it, would I just click the X next to it in the image menu?

Thanks!