facial numbness is a potentially serious symptom tht could be due to things like strokes, Bell's palsy, facial neuralgias, etc.
See Your family MD and an Eye MD ASAP. Find an Eye MD at www.aao.org
JCH III MD
Not to scare you, but my mom had the exact same symptom you are describing and dr's told her it was stress related. They gave her anti-anxiety meds and sent her on her way. When her symptoms slowly began progressing, I took her to an ER and she was diagnosed with a brain stem tumor. Have this checked immediatley! Better safe than sorry.
I'm a lay person, but you should have it checked out by your doctor.
However, that sounds like the Bell's palsy that I had several years ago. It started with a twitching eyelid that lasted for 3 or 4 days. Then I experienced hyperacusis on the same side--my hearing was overly sensitive and certain sounds actually hurt my ear. Then I got tingling and numbness in my lip and check, and eventually the whole left side of my face was paralyzed. I couldn't shut my eye or blink, smile on that side, etc. I was fortunate that the paralysis went away after two weeks, but I continued to have occasional pain and tingling on that side. Six years later, That side of my face is a little different than the other, a little fuller looking, a little "laxer," and I will occasionally get some fleeting pain or tingling in my ear and face.