Breastfeeding- 1 week old HELP

So while in the hospital, the nurses told me that my son is a "lazy" eater- meaning he doesn't want to do the work to be fed. He was hungry and would latch amazingly but wouldn't want to have to suckle.

I continued to try once we were home and it got a lot better once my milk came in.

I read that some moms are nursing for like half an hour or more. My son only nurses for like 15 minutes at the most. Then he either falls dead asleep (even though I know he's still hungry and will look for food the minutes I out him down) or he pushes away. When he falls asleep at the breast, I try to wake him by burping or bouncing him or nudging him- anything! Usually it doesn't work.

I want him to be able to stay latched and nurse longer.