How much to feed?

Anam • PCOS, Baby Rayaan Feb 2018❤🌞, EC since birth, BLW

We just started EP about a month ago now since my supply dropped and he wasn't latching well and I got really concerned about his weignt. LO is now 3 mos and Ive started feeding him 5 oz breast milk every 2h usually about 6x per day. so about 30oz total. Is this too much? Sometimes he takes very long to finish a bottle and I have to really coax him into finishing the bottle. Is bottle feeding breast milk different from feeding formula as far as how much they should take or how often ? thanks for reading