Text in green are more natural ways of saying the highlighted text.

I started to speak in English 6 months ago. Before then I had thought it would be unnecessary in my life but now I work in Thailand with people from various nations in English. 

Anyway, what I want to say is that sometimes I speak English without feeling and deep thought without thinking to respond immediately, so it could lead to rudeness. When I speak English, I am absorbed in making correct sentences in my head so that I often forget to ask something sensitive more politely and indirectly in a more polite manner.
For example, in the past, I have said to my coworker "you look serious while you are working". Even though it was my first to time meeting her.
Oh... after that it has been hard to talk with her. I just wanted to lessen her concern.
Actually, I don't take that way to ask like that, talk like that when I speak my mother tongue.

Do you guys have a similar experience?