Your anxiety and thoughts that your life will be completely over if you fail here and there...are not helping anything. They are even not true. If there is an exam you fail you can try again a little later. Can`t you?..i know there where i study there is a possibility like that.

The real question is: Do you love what you do? Are you sure that THIS is what you want to do with your life? And if it is - it doesn`t matter how many times you fail...and whether you get a scholarship or anything...what matters is that in the end, you win. You don`t have to tell your sister about every test. If you love it enough you will do everything it takes...if not you will leave it with and understanding that it is not your way...and there are other ways better for you..

You see - when your emotions are interfering in your study process - your cognitive process becomes slower. Silence is what you need. Creative thinking, and fast thinking - that stores in your memory whatever you learn, and pulls it out faster when you need it - doesn`t work the same way as emotions do. Your friend may have more "tallent" than you do, but i bet that he/she takes everything in much lighted mood . If it is a threat on you - then you experience it as something "bigger" than you are. Not something that you do, that comes from you. But when you write an paper or a test these actions come from you..and not to threaten you from outside....

I know how feel....college can be hell with their non human demands...

I hope you have a therapist to help you deal with the emotional part.

and by they way:
DONT DRINK COFFEE when you are exhausted! Yes. Only when you are a bit tired and unfocused. If you slept 3 hours - all it does is give you more anxiety and pressure... or a high...you sound anxious enough without that.

You run to get help, drink coffee, sleep for 3 hours - like those all too good girlfriends who find their efforts are not appreciated. I think that if you put less effort and more fun and creative thinking... you will see better results. Like those *****es who`s boyfriend is at their feet... be a little more "*****y" to your studies...if you cared LESS about it what would have happened? you can imagine for a moment

I really hope you will get help, even a friend to talk to. Because you can be efficient when you are at peace. Focused. Not when you are anxious and desperate. Get 8 hours of sleep like you friends does. Whatever hurts or threatens you does not good but to force you to act out of fear - and this happens when you don`t enjoy what you are doing

Take care