Hello, I Am 18 Yr Old Female, 167cm . 5yr

Hello,
I am 18 yr old female, 167cm . 5yr ago I began on a severe diet cutting of all kinds of foods gradually till at the end I ended up only eating fruites, skim yogurt and liters of water and green tea, litrally. This lasted for about 1yr and a half, I had reached 46kg(from75) by Augest 2013. Then I relapsed totally , Now 8monthes later I am back to my old weight only to be worser in eating, For the last 2monthes or so I havent eaten only junk food and fast food, litrally.
I never had any sleeping problems or headaches before even when I was deiting.
Now rarley to I get a good refreshing deep sleep and even more rarley to I wake up without a pulsing headache all over the sides and front of my head. Also I wake up and my throat is full of green _yellowish mucos that I need to spit out. I have a sinus problem that keeps coming and going (I litrally never ever had flues not when I was fat 75kg nor when I was deiting),I have changed to sleep on the opposite side of my bed and I am not hard working as I used to be, you see I am a medical student that has long ago set high goals and hopes for my future.Today I cannot think of anything much but that I have a seriuos problem that will kill me any second. This is destroying my life and goals.
Do you think I have a serious problem???

Regards