Hi Marci-
Just saw your post and wanted to respond. YES, your face will be "droopier" when you are tired, and your speech may also slur. Mine still does. You may find that Ps and Bs are particularly tricky - these are very hard sounds to make if you can't purse your lips.
I did see a speech therapist (I make my living talking, so slurring for life wasn't an option!) and they gave me some specific exercises to address this. They also recommended tongue twisters to help me with the slurriness - I still do Peter Piper Picked a Peck of Pickled Peppers and Betty's Bitter Batter almost daily. And, as I have gradually gotten some movement back in my face, the slurriness has gotten better - still a problem when I am tired, though.
For the general numbness on your face - my surgeon recommended warm compresses and that does seem to help. Interestingly, the facial therapist I saw also suggested taking a very cold metal spoon and running it around inside my cheek and gums - she said it helps to stimulate the nerves in the face.
I'd be happy to send you the print out of the exercises I am using, if you'd like. Just PM me with your address if interested.
And, be patient! I just posted some pictures on my blog from this weekend if you want to see how my face looks 3.5 months post op.
Debbi, feeling your pain!