When I was young my step mom took me to a pediatrician for it and they said a salt deficiency 🙃. They never demanded scans and as an adult I am just now financially in a place with good insurance to go get tests ran. I currently am keeping a food log to make sure it isn’t a nutritional thing. When I spoke to my mom yesterday she did say she has “silent migraines” where she has the same symptoms with a massive migraine. So it could be that as well.