my cat got out and now is acting crazy

[Karen]

First, some questions:

How old is she?

Why is she not spayed?

Did this happen today?

It sounds like she may have been injured if she reacts strongly when you touch her back. She needs to see a vet as soon as possible.

[Catlady711]

She needs to see a vet as soon as possible.

I agree totally. Acting in pain is a sign she needs medical attention. Fight wounds aren't always obvious and can turn into an infected abcess days or weeks later.