Replace the last part with that:
int n = 0;
for ( n = 150; n > 0; n--)
{
delay(150);
if(n > 99){
lcd.setCursor(13,1);
lcd.print(n);
}
if(n <= 99){
lcd.setCursor(13,1);
lcd.print("0");
lcd.print(n);
}
if(n <= 9){
lcd.setCursor(13,1);
Serial.print(n);
lcd.print("00");
lcd.print(n);
}
}