Pushups! (question)?!

Pushups! (question)?

My chest doesn't hurt anymore from doing pushups. Are my chest muscles still getting worked?

Unless you're in a jail cell, stationed out in the deserts of Iraq, or just plain bored, there's really no reason why you should be doing push ups in the first place. They are an acceptable 'burnout' exercise, but that takes place after a genuine chest workout. Join a gym and introduce yourself to a bench and a barbell if you are truly concerned with working your pectorals or 'chest muscles'.
If you're a push up fanatic and won't listen to reason, try placing three chairs together in a triangle formation, with your feet on one and a hand on each of the others (in the same manner you would do a normal pushup). This will allow you to dip below the level that you normally go and thus increase the difficulty. Beside doing pushups between two chairs, you can also try triangle pushups which are performed by placing your hands together (your thumbs and forefingers forming a triangle - thus the name). This close 'grip' will work your triceps and inner pecs and are much harder than a standard push up.