A little bit of my frustrations

I just got started with a new job last Monday. I was afraid for my English level since at this company I must speak with native English speakers every single day and that is a challenge for me, because this is the first time I have to do this, and I feel my English is really bad.

The last Friday I had a diagnostic test to check my English , it was with a native speaker and it wasn't easy. It covered speaking, writing and listening. After this test I he said to me that my English level is like intermediate. I  was a bit disappointed with the result, so I have to improve my skills in this language and right now I am practicing and leaning more vocabulary and finding a way to avoid the fear I feel each time I speak in English.

My coworkers have a really good English (or: my coworkers speak English very well) , I am really impressed with this so I want to be at the same level that they are.

Very good. With practice, you will speak at the same level as your coworkers.