I'd also suggest *filming* yourself with a camcorder.
My father did this to me very recently at a party where I sang for a little film to be sent to other family in the antipodes.
I was happy with most of it, but negative traits I noticed in particular included where my volume decreased significantly in the lower registers. And also an awful lot of twitchy discomfort was evident, in the form of lip biting and similar.
A helpful experience to both *hear and see* myself.