Yes, that's more or less how it feels :). When I write in English, I think in English, when I write in Polish, I think in Polish, and it's very hard to re-create the process and find things that would mean what I want them to mean and be correct at the same time. I tried it once, a friend corrected the English version, and now the fic's been waiting for a month, because in order to make everything right, I have to forget the Polish phrasing. It's easier from forgein to native.