My dog have Parvo,or Worms?

He keep throwing up,it's clear and foamy.I saw a worm in it.His poop is bloody and wet.He lost ALOT of weight.He won't come out of his bed.He's a tough one.We gave him medicine and it's not working.I keep crying and crying.Though he's the one sick, he tries to cheer me up.He chases his tail and lays next to me.That don't change the fact he's sick.We got a appointment for him. What to do till then?