You did great!

The only thing you're doing now is giving too much thought to what your other co-workers think, which you shouldn't need to care about at all. I mean who really cares what they think, right?

But to that point, the way they were acting is usually either out of envy (wishing someone would like them like that), or just being excited seeing two people they know maybe start to like each other. People just want to be part of that for some reason even if they're not really involved. You see this a lot on school playgrounds and stuff like that, and it really just boils down to people enjoying drama.

Anyway, forget them, they're not worth your thoughts. All that matters is your interaction with your friend, and it's great that you didn't let other people take that from you. :)