If that is your only symptom, and it is an isolated event, I probably wouldn't worry too much. Especially since you are tired and stressed, because that can affect your body in very strange ways.
But, if doesn't go away I would have it checked out. It could be something neurological. I say this because I have epilepsy and that sounds very close to what happens to me before a seizure. The right side of my face starts to tingle, and it spreads down my neck. My mouth also seems to be paralyzed.
I hope this didn't scare you, that is not my intent. If you have any questions feel free to ask. My advice would be to be aware of it, but don't worry. Get some rest and see what happens.