Is it normal i hold my breath when i walk past people

I do that exact thing. I don't want to breathe in their exhalations. Also, when people cough or sneeze near me, I hold my breath. If it gets too much to handle, I will walk or turn away from them to quickly breathe in clean air, or I breathe into my bendy part of my arm.

It is ok. Unless you visit chinas capital. :D Please don't do that! XD

Normal. Chances are, they stink.

lets hope you dont get stuck in a crowd

Me too!

I used to do this ALL the time.

Sounds like you have anxiety issues. you should breathe. :)