Wow, well...she's gone. Her name was Emo...it was pretty fitting because for a long time after I got her she'd just sit in the corner "crying," as we used to say lolll. She opened up a ton after about a month of being here.
I went to the vet after posting here and the e-vet saw her asap...but didn't do much. She game me some fluids to administer and told me to keep her warm. They also gave her an antibiotic. After getting home, I gave her the fluids, medicine, and wrapped her in a blanket to keep warm. She was quarantined too, of course. Anyways, about 10 minutes ago I just hear this violent shaking coming from the cage, so I run over to see her just completely spasming and urinating everywhere...then she lay still. And that was that, she was gone. It's weird...this must have started last night and through this morning, both times during which I didn't really have a chance to interact with the rats. They're in my room and all..but I just walked by, took a shower, sat on the comp or read a book on my bed, left the house, etc. I usually play with them the most in the evenings. And she was showing no symptoms last night. Still very confused...though I'm pretty sure rats are really good at hiding a lot of their ailments.