Hello from JustAnswer. This is Dr. Love and I will be helping you today.
Generally speaking, someone that has vomited blood three times should be seen. There are many possible causes of vomiting blood,m but the most common cause would be from an acid irritation syndrome, such as ulcers or gastritis. It is also possible to vomit blood from a abnormal blood vessel or a tear in the esophagus.
The back and neck pain can be muscular pain or it can be referred from the GI tract, but the back and neck pain is not as worrisome as the vomiting of blood.
Since you are on vacation, it would be better for you to be seen in an Emergency Room or an Urgent Care Center, but at this hour, it is usually only an emergency room that would be open. If you are in a location in which it is not practical to be seen quickly, the best that can be done without being seen would be medicines to suppress stomach acid, such as omeprazole, until you can be seen. It would be better to limit medicines for the back and neck to Tylenol, as other medicines can irritate the stomach.
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