My son is a bottomless pit, am i overfeeding?

Erbear
So we started feeding my son solids around 4.5months because he was having a hard time gaining weight and the doctor thought he needed more calories. He was instantly a fan. I was EBF in until that point. Since then I've also supplemented with formula, maybe 8oz a day of formula. I already nurse him first, then offer food about thirty min later. Formula is offered two or three times a day after we nurse. What I'm noticing lately though is that my little dude seems to have a bottomless pit for a stomach. He's six months and I swear I can nurse, then offer four oz and then food and he eats it all. I was offering him one ice cube size of pureed food but now it's up to two. If he's that hungry, I'm all for giving him what he wants, but I'm afraid I may be over feeding him. I'm also afraid that bc of the food and formula my supply will just disappear. We've tried pace feeding with the bottle for formula, it doesn't seem to make a difference, he'll always finish it, even though he seemed content after we nursed. He also seems fine with four extra oz in him, isn't really spitting up or anything. I guess I just wasn't prepared with what introducing solids would be like and he just seems so young to eat so much. Not only that but I know BM should be the main form of nutrition.