Did you overreact? Maybe. However, it wasn't a crazy request. In fact, I'm fairly sure I've seen that in movies.
I think a lot of women worry that men who have just been intimate are in their feelings and make hasty decisions based on their emotions at the time. And that's fair. So asking a man to take some time, and if he still feels the same way in the morning. Or after taking some space for a day isn't unreasonable.
Hell, it might be smart. Though I'm guessing that the majority of men probably wouldn't like being told that because of how much it usually takes us to commit, but if he wanted to be with you, he'd understand and happily oblige. And then you all could laugh it off later.