no expert here either, but is it just me or does he look pretty dehydrated also? judging by his cheek in the first pic and his left eye in the second pic, both look fairly sunken in to me, maybe it's just the pictures though.
either way, get him checked out as soon as you can and hopefully he recovers fully and quickly
I agree, I would not wait 5 more days. The swelling is likely fluid which would mean infection. An eye problem can be symptomatic of other problems like URI (upper respiratory infection). when he gapes do you see any stringy mucous in his mouth? is he showing ANY other unusual signs? He also may have been bitten by an ant or other insect. How long has it been this way?
A really common cause of a swollen eye like that is hypovitaminosis A (vitamin A deficiency). I would go into the vet ASAP. It could be other things as well, such as parasites, traumatic injury, infection or tumor. This isn't really something you can diagnose and treat yourself. Good Luck.