I kissed a friend of the other gender in a platonic way.

I (M18) kissed a completely platonic friend (F27). There was no sexual or romantic intent between the both of us, we just did it in a friendly manner and both of us agree on that. There was no tension between us when we did it too, we were just drunk and thought it would be funny to do it. The thing is I have a girlfriend that I love very much and I feel bad about it as it might come across as unfaithful, what do you guys think? I feel miserable and that I shouldn't have done it even though it meant nothing.