Hi - I've had three babies, 2nd labour was much quicker than the 1st (3rd labour was the same length but so much more painful, think the baby was back to back until just before the birth). I agree that after pains much, much worse - but back then you either couldn't take ibuprofen or I wasn't told. With the third I was told I could take ibuprofen (and did) and what a difference that made, after pains no where near as bad as after second baby, and they do get worse with each one.
Very best of luck - just think of that delicious little baby you'll be holding soon