If you want to figure out what your program is doing with some Serial.prints, it is good that you excluded pin zero from having it's pinMode set, but you should do the same for pin one too.
You also want to look at the state change detection example. Your code, now, will light up all the LEDs in one set whenever the sensor IS high, not BECOMES high.
You need to detect when it changes state, from no motion sensed to motion sensed, so you can count the number of times that has happened. You light a different number of LEDs, based on the count.