If you ain't the limit

Hello everybody,

I am translating a book from English into my own language. And I have difficulty in understanding some phrases. I would be appreciated if you help me. Here is one of them:

- yes. And I'm afraid she will worry, too.
- Gorry! if you ain't the limit.

What does "if you ain't the limit" mean here? Can you write it in other words, please?
Thanks in advance.