I have no idea why you or your gf thought this was weird or creepy. In my experience, tongues are a common part of kissing.
It is slightly odd that you mentioned it though, but stranger that she is bothered. Although perhaps it's something she didn't like and didn't know what to say.

I'll be honest I prefer dry lips on a kids, regardless of wether I am French kissing or not, I don't like coming away with wet lips and feeling I have to wipe my mouth.

I am confused as to why you think all guys have to be a bit creepy. If you could elaborate as to what behaviours guys have that constitute 'creepy' that would help a lot.

All the best.