Work anxiety all or nothing thinking and panic.

Hi All,

So to give a general description, I'm apparently doing ok according to my new employer, indeed been told im 'really good' from them and given plenty of room to manoeuvre - all good , but got several critical emails from client with 'i'm dissapointed' in it.. ( this to me is game over, all or nothing thinking, just find another career) but i understand its typical language and not personal but inwardly I really can't compute the difference. I'm riddled with anxiety, i don't feel that i am really navigating the cut throat business world - i'm just trying to be the honest me (im *** otherwise) which i think puts me at a disadvantage. 

I feel I need to correct this soon or I am going to fail somehow and i'm anticipating losing my job soon. I'm wondering how others deal with similar negative feedback despite doing your best.