I'm having a hard time finding if there's a word for this...

I had my boyfriend over Friday night, we had a lovely time, and when I dropped him off at his on Saturday afternoon, I just immediately felt empty and restless. I couldn't stop thinking about why we weren't still together and assuming it was because he was tired of me or hanging out with other people and he didn't invite me or something (when in all likelihood it's just because we'd just spent a lot of time together and he has healthy boundaries). I went to a store and bought some random garbage and ate some junk food and drove around and sang loudly and then I felt a little better but I was still pretty distressed for a while there.

DAE get this? Know what it's called? Have a good way of dealing with post-hangout bad feelings?

Thank you :)