Infant feeding, is this okay?

So my baby is 5 days old and came 2 weeks early through c section due to preeclampsia. He has a little jaundice and I was told to supplement with formula as well as breast feeding to help him have bowl movements more frequently. Today I’ve noticed he’s wanting to eat almost every hour and like 2 ounces each time. So I’ll use my breast milk but then he’s still hungry so we give him a little formula. An example is earlier today he ate bottle I pumped that had like 30 ml. A few mins later he was eating on his hand so I gave him a small formula bottle and he wouldn’t stop until he ate 40ml. Then an hour later he was hungry. Is this okay? He has an appointment Thursday and I’m definitely going to ask about all this just figured I would try for some advice on here also.