The diarrhea is one of the typical symptoms of acute radiation exposure, but the nosebleeds aren’t. If someone had a sufficient exposure to cause diarrhea, then hair loss should have followed by now.
Actually, according to Wikipedia (http://en.wikipedia.org/wiki/Acute_radiation_syndrome), “bleeding due to low platelets” is a symptom of acute radiation sickness.
Also, the wikipedia text has only one reference to hair loss as ‘very large skin doses can cause permanent hair loss’.