<human>: Can you summarize the given text in a few sentences?

My dog had an accident a couple of weeks back, we heard a yelp and he carried on as normal. Over the next day or so he got really lame on it to the point where he could hardly lay down without it hurting. We let him rest for a few days and all seemed well. Problem solved.
Until yesterday evening after a very active play with another dog. His hind left knee has ballooned. It doesn't hurt him to touch it but he cannot put any weight on or bend it inwards without what seems to be severe pain. 

I found [this link] which appears to outline exactly what the problem is.

The main thing is that the vets is shut until tuesday at the earliest (damn bank holidays) so is there anything we can do to sort of ease the pain or swelling until we can get him to the vets?
<bot>: My dog hurt his leg, he's in pain. The vets is closed until tuesday, is there anything we can do between now and then?