I've been speaking English for two thirds of my life, studied it in university and now work as a translator. I consume nearly all my entertainment media in English. My (formulated) thoughts freely switch between English and German, partly depending on which context I'm thinking about.
Replace German with Estonian for me and we're good. Well, almost, probably closer to half my life instead of two thirds. Had a period during school time where I was also often using German for both thinking and talking to friends as we were mostly watching German TV at the time. And, weirdly enough, despite very little knowledge of it, I sometimes also slip into Japanese nowadays when it comes to thinking about related subjects...