I've done the same thing and had the same fears, but my T was so comforting and validating she actually thanked me for writing my unedited feelings. She even told me that while she was reading my email she actually had the reaction of "Ahhh there it all is" meaning that although I've gotten better opening up I still edit myself in sessions. She actually really appreciated receiving the email because it gave her a great understanding of my feelings which in turn helps her to help me.