Ay, napakabait ng kuya mo na bantayan, pero ang ingat talaga with babies drinking while lying down! Since nakabili lang ng kaunting tubig at umubo lang siya pero okay naman after, pwede mo lang bantayan closely ngayong gabi, kung normal ang tulog niya, normal ang breathing, at walang unusual cough, likely okay lang siya, pero kung medyo concerned ka pa rin o may persistent coughing, better to message your pedia or have them checked bukas just to be safe, kasi puwedeng may maliit na tubig na napunta sa wrong pipe and we can't really tell. One of my mum friends' baby din nangyari yan at fine naman siya after, pero ang sabi ng pedia niya always feed baby upright talaga para safe, so for next time, kahit gaano kabilis pumayag ang kiddos, sit them up muna bago uminom. You're doing great being alert, mommy!