Baby eating too much?

Elizabeth

My 15 week old has been taking 4-5 oz every 3hrs. A total of 28-32 oz a day of formula. Well in between feeds he is very adamant about breastfeeding. I try and up his bottle amount but he doesn’t want it. He only wants breast milk. Idk how much he’s drinking since I never really established a supply I just gave him some whenever he wanted it. The reason for this was that he didn’t latch at all for the first 2 months and when he did he never seemed full enough. He was born at 6lbs 14oz and now he’s at a whopping 15lbs 4oz. I’m going to bring it up to his pediatrician on his 4 month appointment but I just wanted some input as well. Am I over feeding him? Or is it ok for me to breastfeed after bottle feeding? I’m just confused.