I haven't spoken it, but I've had times where I've referred to myself in my thoughts as "she." I've determined it's mostly because a lot of the time when I'm mentally thinking about explaining things I think as though I'm talking to someone I know, and that person is normally someone who calls me by she/her/hers pronouns. Now that pretty much everyone is calling me by my proper pronouns, it happens a lot less. Just one of the things that takes some time to adjust to, I guess.