Baby random shaking episode

Freaking out. My baby will be 4 months old in a week. She’s developmentally been right on track and a lot of her old quirks have disappeared like lip quivering and other random nervous system things that develop. This morning I drove her to my mom’s to drop her off before work and she woke up in the car seat as I was carrying her in. She was smiling and looking at us and as I went to unbuckle her I noticed her head shaking/bobbing almost looked like Parkinson’s disease. She smiled and acted completely normal- it happened for 20-30 seconds… then we got her out and it stopped and she’s been fine ever since. I’m at work on absolute edge that something is wrong neurologically or she has meningitis. I know infantile spasms usually have the rigid arm movements and stuff and I haven’t noticed anything like that. Just looking for advice or other moms who might have dealt with this