I suggest to start with the code provided in that tutorial, and learn how the sensor actually works.
The following reads the shock sensor for about 62 billionths of a second, every two seconds.
How do you imagine that will work? (Hint: don't ever use delay(), if you can avoid it).
delay(1000);
shockVal = digitalRead(shockSense);
delay(1000);
Serial.println("shockSense");
Serial.println(shockSense);