Haiz... Test Back

aiyo... im so disappointed with myself. u know y? let me tell u y? this is y... i actually failed in my chemistry class quiz twice... this is so bad...
i fell that my heart got strike by sth sharp.. feel painful...
when i look back on my papers.. i actually can do the question.. bcuz of my careless mistakes again then i end up with a FAIL in my test. T_T i wanna burst out my tears...wawawa...
My class topical test also the same actually i can get about 70++% but i end up by scoring a 60% how can i do this to myself...
who can help me?!?!?!
only me can help myself??
but i've work hard... don't i work hard enough?
it's all bcuz of my stupid CARELESS mistakes again which made me end up like this!!!
I hate these careless mistake!!! :-
*press the calculator wrongly (eg. actually it's multiply BUT i press divide on the calculator!)
*didn't read the questions carefully
*too NERVOUS .. then can think properly even the simply writing of chemical and ionic equation!!) JeeZZ...
I HATE THEM ALL!!!
Tips for myself : read the questions carefully and DON"T BE NERVOUS when answering questions!!!