Gassy baby

Hi mummies is it true that gassy baby will avoid drinking milk when its their feeding time? My 2 month boy refuse to drink and will keep on crying once we put the bottle in his mouth. His on fully formula milk. Its been a week and its going crazy! Any idea is it because of gassiness or reflux? He did not have any spitting but he is fussy during feeding. Can only get him to drink while his sleepy mode. Check with GP no oral thrush but doctor only say milk strike and give me vitamin to boost his appetite. But it doesn't seem like milk strike to me. Should i get 2nd opinion from other GP or any mummies out there experience this.