3 month baby Loose motions. it's urgent.

Dear doctor, My baby is completed 3 months yesterday...he is having cough problem doctor told me to give mucolite, terbex,augpen for 7 days..but today at every 20 min he is doing little loose motions ... When I told doctor he told me to give kidygut sachet morning evening ... But still it's not control... Now doctor again told me to give enterogermina morning and evening 2.5ml.. Now I m frustrated.. can enterogermina will effective for him? Also due to this he is not drinking milk properly.. Plz give me solution...it's urgent 🙏 baby is on Breastfeeding + Formula feeding ...both... because only breastfeeding his stomach never gets satisfied...in 24 hours he take around 350ml Formula milk..and rest breast feeding...