DS is 18 months old and on wednesday morning he woke with what looked like a bit of a black eye. He was then rubbing it all day and seemed uncomfortable with it. No other symptoms. The actual eye is fine, no discharge or swelling, it’s just reddish purple underneath and isn’t fading. I tried to get him seen by the GP today but no appointments till Monday but we’re meant to be going to the Lake District for a week as of tomorrow. I asked the pharmacist for advice and they said they didn’t know and to ask the GP 
I’ve googled ‘allergic shiner’ and it looks like it could be that - does anyone have any experience of this, does it look like it could be that? Does it go away or does it require treatment?
Pic attached (there was no coffee in the McDonald’s cup, by the way 
)