Speaking Up For Migraines

Why do people use the word migraine so casually? Migraine is not interchangeable with headache. It is not some female response to stress. And it is not the word used to describe a woman's headache. Hearing people use it as such is like nails on a chalk board to me.

My husband and I have been taking a social ballroom dance class once a week. The other day one of the women was looking confused about one of the new steps and sort of put her hand up to her face pinching the bridge of her nose and scrunching her face in frustration. The teacher jokingly said something to the effect that it looked like this was giving her a migraine. Obviously what he meant was that it was giving her a headache. 

Not feeling like it would be appropriate to point out his mistake and severe lack of understanding of what a migraine is, I just cringed. Yet another example of how little the general population knows about this fairly common condition. 

I want the public perception and misconceptions about migraines to change but I don't really know what I can do to make it so. Have I made a mistake by not saying anything? I don't want to be that person who kills the fun by correcting a lighthearted exchange between two other people with dreary facts. Even more, I don't want to be that person who can't have a laugh at myself or at my situation. 

Not to over analyze this specific situation - but in general I simply don't have a handle on if and when and what I should say in terms of educating those around me. Is it ever my place to say something? Being unsure, right now I default to saying nothing.

How do you handle situations like this? What do you think would be the right thing to do?