Writing Emails
I absolutely loathe writing professional emails to people I don't know very well (and often even to people I do know somewhat). I get this horrible feeling that everything I write seems awkward. This leads to putting off writing important messages as long as possible, finally spending an hour to write what turns out to be only two or three sentences, agonizing over whether to change anything, and then finally and fearfully pressing the send button as though it were the detonator for a bomb.
Then I can spend days dreading a reply indicating that I somehow made myself sound like a fool. Which, arguably, I am, but not in ways that should have been transparent in the final email.