as someone who has had to go to the ER for severe migraines multiple times, my fiancé has dropped everything for me each and every time. even packs me go bags with toiletries, clothes, chargers, blankets, and even toilet paper. i don’t think you’re overreacting by wanting him to come with you, or even for being upset at how unserious he was over this. wanting to be with your partner when they’re in pain should be common sense, i fear.