Feed on demand?

Rosa

FTM .. My LO is 2 weeks should I still wake her every 3 or 4 hours if she doesnt wake on her own to eat or is it feed on demand at this point? She's eating about 2 oz of formula every feeding sometimes falls asleep before but I try to wake her to keep eating. If she falls asleep before the 2 oz should I just let her be and continue sleeping? Don't want to overfeed or underfeed her.