Blood in the vomit can be caused by a few things.
First, it can be caused by violent wretching--this can cause tearing in the esophagus. This will typically cause pain in the chest and is uncommon.
Second cause is peptic ulcers. This is a potential source in your case given your symptoms of abdominal pain, although the area of your pain (right sided) is less typical. Peptic ulcers usually will cause pain in the center of the abdomen or the left side but occasionally can cause right sided "referred" pain. Ulcers can result from advil/aspirin use, alcohol or from a bacterial infection called H. pylori.
Third cause is bleeding veins called esophageal varices. Extremely unlikely in your case. Usually due to long-standing alcohol abuse or chronic liver disease and bleeding is quite heavy.
If you swallowed blood recently (from a nosebleed
) this could also have caused nausea and vomiting blood.
Any time someone has bloody vomit, it has to be checked out. If you feel normal now, no abdominal pain and no nausea, it can wait until you can see your doctor tomorrow. If you are still feeling ill and nauseated and vomiting or have abdominal pain, back pain, chest pain or dizziness, I suggest that you go to the emergency room today.
You may see black stools over the next day or so. This is also a sign of blood in the GI tract. Don't be alarmed.
I hope that you feel better,
Feel free to ask any follow up questions and I will be happy to discuss further,
If you are satisfied with my help, please remember to click accept.