Well,i Feel So Embarrassed To Talk About This I'm A

Well,i feel so embarrassed to talk about this
I'm a 17 year-old girl...and i always feel horny and turned and this prevents me from doing my activites like studying ,sleeping..etc
I cannot concentrate on my lessons
I can't study
I always feel that i want to be kissed and those feeling although i don't have a boyfriend or in a relationship
It just wastes my time
And i always get sexual fantasies
I dream about sex
I love watching love scenes
This has interfered in every activity in my life and it became uncontrolable
I can't stop this and i can't work on my future and i don't know how to stop these feelings and those dreams and fantasies..it wastes my time
And i sometimes wonder why i'm different from the other girls on my age
I have a high sex drive
I always wonder why i'm not like them
Plus there's another thing that suddenly happens to me
When i sit alone i suddenly get a feeling like my memory vanishes,i start asking weird questions
Where am i?! Who am i?!
What am i doing here?!
And i feel like out of my mind like i literly don't know who i'm
It lasts for some minutes
And then i come back to my ordinary state
It's like a brain disorder or Al-zehimer thing
This really freaks me out
I feel like i will end up not knowing myself
Now would please tell what should i do in both cases...i need help
It's my last year on high school and i can't concentrate on my studies and lessons
Help!!