Hey! I'm sorry you had that interaction with NU financial aid. I went there for my undergrad and while I had a generally positive experience, their bloated admin network/bureaucracy can be a headache to deal with. It's also a little insane and confusing that they have a fully funded MA + MFA and an unfunded MFA so I wouldn't beat yourself up about making that (very understandable) mistake. Grad school apps are hard and messy and I feel like so many of us have regrets about where/how we applied. (I didn't apply to UW Madison literally just because I misread their website and thought they weren't reading in my genre this year. LOL.)
Plus as others have said-- you have a waitlist from JHU and Vandy. You've definitely got something really good going on in your writing sample and you have every reason to stay hopeful, especially with 7 apps still pending. I also think it's alright to feel sad/annoyed/frustrated for a bit. Cry it out, go for a walk, get takeout from your favorite restaurant. Tomorrow's a new day.