Was I the Asshole?

I recently got separated from my wife of five years. It wasn't mutual, she found someone else and moved out weeks ago. We were both in a rough spot emotionally, but it happened fast. I've been trying to stay busy with school stuff here at college. I'm not a party person by any means, but there's this girl who sits next to me in a couple of classes and she seems cool. Anyway, so yesterday after my last class we were walking back to our dorms. We got talking about how weird everything feels now that the whole world is reopening from lockdown. She asked if I was okay since the breakup. I told her yes, but it wasn't really true, I've been feeling lost and lonely a lot. Then she suggested grabbing dinner together at this new Thai place near campus. We started talking more during dinner, she's smart and funny, and before we knew it, hours had passed. She seemed to be into me too; I could tell from the way she was laughing with her hand over her mouth, how close she leaned when making a point. So we walked back to my dorm together late at night. We stopped near the entrance of my building and just kind of stood there for a while. Then things got heated quickly. She suggested going up to my room for coffee or something, but before either one of us knew it, things escalated really fast between us. It wasn't like I planned this, I was just so lost after everything falling apart with my wife and she seemed so understanding and genuine. We ended up having sex in my dorm room, pretty much as soon as we got there. But then this morning when I woke up, it felt weird, like what did that mean? Did I actually like her or was it just about feeling wanted after being dumped? Was it really fair to take advantage of someone who might be seeing me as a distraction? I don't know how to process any of this. Is there something wrong with seeking comfort from another person in the aftermath of divorce, even if it's not an immediate relationship but just an escape and relief from loneliness? I can see why my ex-wife would call me out for being selfish or thoughtless. But I really need advice on what to do now. Am I the asshole here? What did I do wrong and how should I handle things going forward?