Sand boa doesn't want to eat

My female kenyan sand boa has seemingly lost interest in her food the last couple of weeks. I see nothing wrong with her, and she is not in shed. She has eaten like a pig since the day I got her, and has been no trouble before this.

I regret to say that a few weeks ago, I gave her a f/t rat pink. I left it overnight, and when I checked in the morning, I didn't see it, so I assumed she ate it. Unfortunately, a week (or maybe two) after, I found the now disgusting un-eaten pink. It didn't stink, but could that have made her go off her food? (I know I would)

Do female snakes ever go off food in breeding season? She's very young though..

Another thing.. since I got her she seems a little 'loopy'. When I hold her, if her head dangles down a bit, she holds her head upside down, and does kind of a corkscrew thing. She seems to have a few screws missing perhaps.. but this has gone on for months, and she never refused food.

I left her a rat pink tonight.. gonna check in the morning. Hope she eats!

Any ideas?

She did NOT eat. This is frustrating.. I just get one snake well again (I think anyway...) and another one goes off the deep end.