AITAH for refusing to introduce my girlfriend to my son?

My ex and I (29M) had a kid when we were 18. We were both junkies. She (thankfully) kicked the habit while she was pregnant, but skipped out pretty much as soon as she possibly could.

My kid (11M) saved my life. I love my boy more than I’ve loved anything or anyone. It’s always been me and him. My parents help me out when they can, but I’ve spent the last 11 years working as hard as I can to make sure he’s safe, happy, and well provided for.

I started seeing someone pretty recently, about four months ago. This is new territory for me. At one point last Saturday when we were hanging out and my son was at his grandparents’ house, she noticed my lockscreen and home screen. One is a photo of my son with the dog we recently got, the other is of him as a baby. She asked who it was, I told her it was my son.

She immediately started talking about how cute that was, and how she wanted to meet him. I said no. She was confused, and I said I was keeping these two sides of my life separate. Introducing someone new into his life as my romantic partner will likely be, for him, confusing at best.

My girlfriend then went on to say something like “I was being gracious about the whole ‘surprise, I have a kid’ thing.’” That put me off even more. I asked her to leave and we haven’t spoken since.

AITAH here? I’m perfectly fine getting to know people and spending time with them (when I have the time) but that doesn’t include shaking up the life my son is used to.

Edit: I clarified some things in a comment: “For the first two and a half-ish months, things were mostly physical. This is the first time I’ve really been in a situation of getting to know someone on this level in 11 years. It’s also my first time doing it without weird drug bonds and my first time doing it as a parent. I have a lot of hang ups about relationships since my last one ended with my girlfriend abandoning our kid because substance abuse was more important.

Baggage on baggage on baggage. I guess I wasn’t exactly expecting to get married— I’d just like someone to spend time with.”