Re: Was she flirting? I'm super bad at reading the signs!
She could just be nice, its too hard to tell from the information you have given us. Keep an eye out for IOIs (read up on them) they are very telling and they are easy to read. Is she touching her hair? Is she maintaining the eye contact? Is she touching you? Does she smile when she talks to you? Ask yourself these questions when you're talking to her.
Have you started touching her? Touch her and see her response, does she touch you back? (that's when you know for sure the games on). A physical connection (known commonly as Kino) is a surefire way to get her attracted in you and I cannot stress how important it is, its like knowing your times tables . It will keep out of the friendzone for sure, like I said it will build the connect and not will make things awkward such as going for that kiss.
There's plenty of other things to go over and I recommend reading a lot IF you are new but good luck with your co-worker!
I am only responsible for what I say, not what you understand - The proverb of a true activist.
I'm not driven by fear, I'm driven by Danger