I feel normal )) is a normal thing maybe because I have a lot of friends non-native
Not at all.
I think you getting nervous is because you are from a country which is really big, and everybody in your surroundings speaks Chinese. Is that correct? Well, I am just more used to speaking any different tongue because I am from a small country, and when I travel only for a few hours, I must speak another language. But if you will do it more, you will get used to it too, I am sure.
I am from the Netherlands, a few hundred miles to the south they speak French, east they speak German, and if I go a little bit over the water, I am in England.
I'm little nervous when chatting/emailing firstly. But it's because mainly they're stranger. And the facter that he/she speaks foreign language and is from other country comes after that. Once you'll get to know each other, such feeling will fade away.
Nacir made a very good point. You are foreigner to them too. When I made a conversation I found that some people are very nervous when they spoke to me so there is nothing to be afraid from