Breastfeeding

Currently at week 4 with my baby. I have always had a large supply. Was pumping 6oz each breast during my pumping sessions. The past 2days my breast have been almost flat and doesn’t seem like baby is getting enough and he is feeding sooner. He was feeding every 2-3hours for about 6-8mins each feed but he’s been every 1 and a half hour and like 15mins each feed.. is this normal?