Baby not feeding well. Are continued?

Hi my baby has cold and chest congestion, from morning, he wasn't taking any proper feeds normally he use to take feeds every 2hrs ,it's been 3hrs he wasn't hungry or taking so we forcefully feeded him through katori and chamcha he took burped and removed good amount of milk after burp,the milk was very sticky sticky, I am going to take him to paediatrician today, last time I took him he prescribed antibiotics, but doesn't seems much change,Clavam syrup, Crocin syrup, ascoril syrup all 3times (2.5)ml,ascoril (1ml),can you please guide can I do forcefull feeding after 3hrs? Or do I wait for him to be hungry and rather wait for 4hrs??? Or wait for him to be hungry, currently he is ill but active and playing, but not taking feed, I want to know the sticky milk which came out after he burped was the congestion which came out? Please tell, do I ask my doctor to change the medicine will it have any side effects if antibiotics are continued??