aerated

In British informal usage, 'aerated' describes someone who is wound up, flustered, or irritated — essentially the opposite of calm. If someone 'gets aerated' about something, they're making a big deal of it, getting hot under the collar. The metaphor presumably comes from being 'full of air' (i.e., puffed up, overblown). The technical sense — infused with air or gas — also exists in chemistry and food science contexts. The slang sense is common in northern English dialects and remains in active informal use.