Sunflower oil??

This afternoon I took Cole to the paediatrician for a check up to see if hes put on weight at our last appointment he weighed 3.00kg and today he weighed 3.05kg so he still has not put on weight and on friday he will be a month old so the paed is still worried, she says he looks happy so she cant understand why hes not eating, I was giving Cole 50ml of formula after each feed but he doesnt seem to like the formula and spits it up so now she wants me to rather give him 20ml with a drop of sunflower oil in each bottle to help him build up calories so please pray that this works. If he doesnt put on atleast 250g by next week monday they will have to admit him into hospital and run some tests so please pray that this doesnt happen!! I know this is going to stress me out this week so Im going to def be on weight watchers this week, my boy I wish I could feed you one giant chocolate please eat lots this week : )