Lost whole email while deleting a small selection of 3 words!!!

I was editing an email previously saved to the DRAFT folder.  I wanted to CUT three words and then PASTE them in another area of the email but there was no CUT function available (problem number one).  So I COPYed the selection and pressed the delete key on the keyboard and the whole email disapeared.  Then I then tried to UNDO but it did not undo the deleted email.  This is repeatable so it should not be difficult to observe.