Dani's a speed-nurser too.....I've met several BF babies that can get the job done in 5min or so after the nursing thing is down pat.....
You know they're getting enough hing-milk by the poop: bright yellow & full of seeds is perfect......they "seeds" are actually globules of undigested fat from the rich hindmilk. If the baby is gorging on foremilk only, the poop won't be seedy and can even lean towards a greeny color.
I know Dani's getting pleanty of hindmilk because she's very seedy....even though she rarely takes longer than 5 min on a side!
Be thankful it doesn't take you long to give your son the nutrients he needs - you could be stuck in one place for 1/2 hr at a time instead!
Shannon