what I'm describing is similar to the muscle spasms you might feel in your arm or leg a few times every year. the last three days I've been experiencing muscle spasms regularly (dozen times per day) on my right eyebrow region. like a worm wriggling around beneath my skin for 0.5-1 second duration. Doesn't hurt or anything, but I've never experienced spasms in my eyebrow before and I'm concerned.
What could be causing this?