He had a mild allergic reaction to fly bites and I called the vet out to check for any respiratory reaction (and just to confirm that it was bites).
Now he has a swelling on his eye (bottom eyelid), there is some tear fluid coming out. Yesterday he had some gunky stuff, I don't know if that is anything to do with it, there is none now. I don't know whether it is a bite, he has bashed it or an infection.
Is there anything I can do for the time being? I will call the vet tomorrow (unless it is better).