Limping dog

I just got home from school and my dog was really excited as usual, then all of a sudden he couldn’t stand in one of his legs anymore and just kinda fell on his side. He’s a 8 years old small yorkshire terrier. I cant get an appointment at the vet until like next week so idk what to do. Right now he’s just laying down and is very close to me at all times, I carry him around cause he can’t really walk but he isn’t acting like he’s in a lot of pain. I can’t see anything wrong when I look at his leg so i don’t know what i should do. Any advice would be appreciated.