Twitching around your lip that comes and goes, lasts only seconds, and shifts between sides is usually a benign muscle twitch rather than a brain problem. Anxiety and poor sleep are common triggers, since both make small facial muscles more irritable.
Next Steps
Working on your sleep and cutting back caffeine often helps, and the twitching usually settles once anxiety eases. If it continues for several weeks or spreads to other muscles, get it checked.
Health Tips
See a physician or neurologist soon if you notice drooping, slurred speech, or weakness on one side of your face.