In the most commonly used contractions - the word 'ain't' is the most confusing one. It's not documented with the textbooks, yet commonly heard on TV.

Before we look at ain't , let's review the common contractions.

hasn't, Haven't, hadn't

Aren't, isn't

Don't, Doesn't, Didn't

There is no contraction for am not. It simply reduces to aren't.

" I am the owner. Am I not ? =  I am the owner. Aren't I ? "

Ain't is a slang

Ain't is a slang that can be used as a contraction for anything. Elite class doesn't use it as it's a slang. Never use it in good social standing.