Sexual Advice with Girlfriend -eating cum

So I ask my girlfriend last night via text because I'm away with work for a couple months, how she would feel about me licking my own cum off of her. It's something that I haven't thought of before but last night it came to me as something that might turn her on. When I asked her she didn't seemed bothered by it at first but then she went very out of character very quickly and went to bed. I don't really know now if she would be okay with me trying it or not, or if now she is having doubts about my sexual orientation