What are the proper tests to have done for someone who has had a nose bleed, fainted and headaches?

My daughter, who is 14, had been having headaches for about a week when she suddenly fainted at school. I had her taken to the hospital for some tests. All blood tests show everything's normal. the MRI showed everything normal. this was all withing 2 days in the hospital. she woke up for school the next day after coming home and had a nose bleed, not gushing, from one nostril (right side). I'm very concerned and stressed.  She's scheduled to have an EEG done in a few days.  Will the EEG help to reveal anything? Should I request something more specific to help locate the problem? I'm desperate, please help me. What are the possible things wrong with her?