Engine power on 2006 Honda Civic Si

My mannual transmission civic power is very weak even in the first gear. Seem like the car is towing something heavy.
What is the possible problem?

Asked by for the 2006 Honda Civic Si
is the clutch slipping?? do the rpms raise but the car does not make it up to speed??

Yes, the clutch is too short..only at the starting point i need to press the gas in order to get the car move
1 more answer , 3 more comments
Is the performance low through the other gears also?
Is the Check Engine Light on?

seem to be like that even in the higher gears...rpms high but the speed doesnt increase unless i pres the gas slowly then the speed would adjust. the check engine light doest appear
Time for a clutch job. Get the rear main seal replaced while they are there.

thanks for the advices.