There is a real term, but it's not a formal diagnosis. Not that we could give that here anyway, but you probably won't find a psych willing to, either. The advice I've seen, for people who do want to get help from a professional, is to print some of the available information and take that along to show them that MDD is being studied, even if it's not officially defined at the moment.
I relate to everything in your post, KelseyK, except the acting stuff out. I do move my hands sometimes, if I'm gesturing in the daydream, but that's all. Everything else, spot on. And I've been doing it for 25 years, so if you can maintain focus in the real world, I highly recommend it. Not that I'd've cured cancer by now if I didn't have it. But it has had a big impact.