Help me Dana!!!

Hey Dana!!! So, awhile back, I changed my background on my blog using the cutest blog on the block that I saw on yours....well, it worked for the first two or three changes.....and now, it's not. My template has been changed to minima, and if I refresh my page while I'm on my blog, it flashes to the background I've been trying to save but then it goes to nasty pinkish, brownish ugly THAT WON'T GO AWAY!!!!! WHAT am I doing wrong???????????