I've seen a lot of people with simillar problems. Basically, I think about most of the things in English, rather in Czech, which is my native language. This also includes made up coversations with people who don't even speak English and sometimes I don't even remember the Czech word (e g. I didn't remember how to say "quiver" in Czech numerous times).
If I was to, let's say, write a romantic message to my crush, I would instinctively make the words up in English, realize she's Czech, try to come up with as nice words in Czech and fail miserably. If I sent her the English message, I know she would get, if not completely understand, what I'm trying to say, but it would be wierd and most likely awkward.
Should I go for it? If not, what should I do?