There are a number of sleep disorders, other than obstructive sleep apnea, that could account for the need for supplemental oxygen at night. If only to be delivered at night, a tank would be an acceptable oxygen source.
But, in addition, you should request a more detailed explanation from your doctors about what is actually causing reduced nighttime oxygen levels. If your doctor is unable to provide that explanation, you should consider consultation with a Sleep Disorders Physician Specialist.
Do not hesitate to ask a lot of questions, until you get satisfactory answers.
Good luck
will i need to see some kind of speacialist? Will mt tiredness agitation and morning headaches get better?
sorry for my spelling