My 16-year old daughter is chronically fatigued. She wakes up a few times per night but does go back to sleep. In addition to these issues, she has not had a period in 2 years (is not sexually active). She took birth control to start her cycles and it did. When she stopped taking the pill, she stopped again. Her thyroid was checked, last year it was borderline high, this year normal. I ve had her checked for mono, negative. Checked for anemia, negative. She has had weight gain which she cannot lose. Her CBC is normal. I don t know what could be going on or what to check