Clarification regarding health.

Hi , My son is 29 days old . He was admitted in hospital on 5th day from his birth for phototherapy due to jaundice (14.6%). Later it came to 11.9 and was discharged .Again we found the mucus in stool and he was pooping watery sometimes and normal sometimes with a bit of fever when ever mucus appears in stool.Doctor on consultation told that it might be due to lactose intolerance and asked to stop breast feed .but we couldnt stop that as baby was unwilling to use zerolac . And again in recent check up we found that jaundice has again increased and reached to 12.8 .Is this because of which he is getting mucus in stool and from past three days his poop his greenish yellow before which it was yellowish.I would be greatful if you could clarify my confusion.