I had a sudden allergic reaction in my eyes last night. I'm allergic to cats and pollen and my cat came in covered with pollen, and I touched her, so I'm guessing that was what caused it. It's not unusual for me.
What was completely new was the bruising that started in one corner of my eyelid, and has spread across overnight to produce the delightful eyeshadow attaches.
Does it need medical attention? I don't see what they could do, it's just that I've never had anything like it and everyone here is telling me to get it seen.