4 day old baby, still no supply

My baby is 4 days old now and my milk still hasn’t come in. We have switched to formula for now because he has to eat something. I’m trying to pump to stimulate production because having him nurse to stimulate is not an option right now. He has a great latch according to the lactation consultant and nurses, but my nipples are now bleeding and scabbed from him trying to get milk out when there’s nothing there. Poor baby just wants to eat. I’m very sore and getting discouraged and need some advice.