Basketball

I have been playing basketball from primary till now...
oh, so long...
but don't know y, i always have no confidence during d match..
especially in final...
when i don hv confidence,my stamina will decrease immediately...
when i think we have to win, bla bla...
I will start to afraid....
that's make me always regret after d match...
y i din maintain my mental for the last second?
y Y y??????
I think i always make my team lose...
That's make me feel want to quit from playing basketball...
I really don't like this feeling...
but i noe i won do that coz i still wan to play...
but i really hope that i won't lose for my mental....
Can I do that?
Thinking.......