What do i do about this horrific situation? *Sorry it's very long, PLEASE READ*?

[pinkgirl]

I am in desperate need of help right now. This is going to be quite long so i apologize but anyone on yahoo answers who sees this question, please please read it because i am in such despair over my situation. I'm a 15 year old girl and i was diagnosed with an under-active thyroid (hypothyroidism) in March this year. Ever since i have been on Levothyroxine tablets which have given me severe insomnia which gets worse when i increase the dose, and it went away when i had to stop taking the tablets. I have been referred to a sleep clinic and they said they will need to do an overnight sleep study on me (a polysonogram) I have been waiting months for that first consultation, i waited 4 months to get there, and 4 months being ignored by doctors because not many people get this side effect. The situation has got so bad that i get 5-10 minutes of very light sleep each night, i only get micro sleeps. I am so exhausted i am totally immobile, i fall over if i stand up and i have not been to school in 6 months and i am missing my exams. I was utterly devastated today when i got a phone call saying my sleep appointment was January the 10th. For months i have been suicidal because of utter sleep deprivation and i cry every single day. I refuse to accept that date, as anyone who saw me would see that i cannot physically go on living like this anymore. I phoned and begged them and cried down the phone to please make it before christmas, or any sooner and they said they are fully booked up and no doctors work there at christmas. So i suppose my question is: What the heck do i do? I dont want to sound like this but i will most likely end my life if i cant get help soon. Could i just go back to the sleep clinic with no appointment and demand they see me? I don't know what to do, i am so sorry that this is like an essay! Like i said i have no one else to turn to, and my life is in turmoil to be honest. Please please help me.