Was I being a creep in this situation?

I (33m) feel like I may have been a creep this morning with a coworker (30f). If I was I would like to change my approach as I don't want to make people feel uncomfortable.

Background: She had just got back from a vacation and works in a different department. We are on friendly term.

The conversation:

Her: Hi.

Me: Hi. Your back.

Her: Yup and your stuck with me until Christmas.

Me: I am ok being stuck with you.

Her: Have a good day.

Me: You too.

She made a bit of an awkward face when I said I was ok being stuck with her. It is one thing if she doesn't have feelings for me, I am just afraid of being a creep. Another coworker I am close with said she thought it was smooth but I am in my head and think she is saying to to not discourage me from trying to put my self out there.

Any feed back is appreciated. And I will do my best to answer questions if need. Thanks in advance.