Why does my dog have bloody diarrhea and is vomiting so much!?

I'm not a vet...but yes, if a dog gets dehydrated from sustained vomiting and diarrhea (like you've described) it can be life threatening. It really sounds like you're going to need to see an emergency vet.

Now that it's 10AM, you may be able to talk online or over the phone with a vet for no charge. Try Google free vet (there are many options that will appear: phone,online,advice,etc. ) They will review your dog's symptoms with you and try to best advise you.

That dog needs a vet! whenever you see blood it's a bad sign! it could be something really bad that they ate ,it could be worms , a parisite, cancer, many things that aren't good. And sence it's been going on for a couple days now, your best option is to take them to a vet and pray.