From the age of around six, I suffered with migraines. These got progressively worse until I was fifteen and I missed over half my schooling because many of these lasted for three plus weeks before I was able to get out of bed, then a week or more for me to fit to return to school.
So, migraines can and do last a lot longer than a couple of days.
A heck of a lot of people declare they have a 'terrible migraine' when they have a bad headache. If they had a 'terrible migraine' they would be in a darkened room, unable to eat or drink without throwing up. Even a mild migraine gives you double vision.
I would think and certainly expect, anyone with Covid 19 working at a therapeutic centre would own the fact so that those in contact would be able to take appropriate steps.