Painkiller Hell Damnation

I've listed the ammo box count you need before each checkpoint, just press back to check before proceeding. The number in brackets is how many you should have found in that section. The secret areas are also mentioned.

#1 - 13
#2 - 27 (14)
#3 - 29 (2)
#4 - 30 (1)
#5 - 39 (9)
#6 - 46 (7)
#7 - 46 (0)
#8 - 56 (10)
#9 - 65 (9)
#10 - 67 (2) * Secret Room
#11 - 67 (0)
#12 - 68 (1) * Secret Room
#13 - 90 (22) * Secret Room
#14 - 90 (0)
#15 - 90 (0)
#16 - 97 (7) * Secret Room
#17 - 108 (11) * Secret Room
#18 - 135 (27 all in the Arena)

Secret areas (credit to painkillerzone)