My dog is vomiting water, has bloody stool, and won't eat. What to do?

Hi there! Let me see if I can help with Bini. I'm sorry she is feeling so sickly. I have to be honest, she does sound like she is quite ill. I would be concerned that she is not eating, and also unable to keep water down. The loose stools are worrisome as well. When we see vomiting and diarrhea together, we worry that our dog has eaten something, and it may be causing a blockage somewhere. The other concern, of course, is an infection of some kind - whether is be a systemic infection, or from parasites in her gastrointestinal tract. Another concern is that Bini is not spayed, according to her description above. In some cases, female dogs that are in tact, can get an infection in their uterus, that can make them very sick too. If she has been in heat somewhat recently, I would put that on my list too.
Regardless of the cause, Bini should be examined by a veterinarian, so that they made evaluate some Xrays of her gastrointestinal system, and first make sure there is not a blockage of any kind. Once that is ruled out, the focus will be on evaluating some blood work, to make sure that there aren't any infections or issues with any of th electrolytes or organs. The blood work will also help to see how dehydrated she is from all of the fluid loss.
Bini will also probably be hospitalized and treated for her dehydration, and with some intravenous antibiotics and other medications to soothe the stomach, since she cannot keep anything down.
Depending on what the veterinarian finds, they will make a treatment plan that is streamlined to suit Bini's needs.
I hope you have Bini examined as soon as possible! Best of luck!