What Causes Light Headedness In 14 Year Old Girls What Could This Be? Please Help?

What could this be? please help? - what causes light headedness in 14 year old girls

14 years old, abdominal pain, nausea, drowsiness, dizziness, headache (probably, I would not always be a headache, because I suffered from migraine), I had this one-off episodes, and perhaps one to three times per week and lasts for one instance up to three hours, I went to the doctor and have blood and urine, said the results I had low white blood cell and reservations, see a pediatrician, but the earliest I could get was at 6 weeks, I am sick and I can wait so long, anyone can help? Ask for more information