Does this sound like silent reflux ??

May spit up a tiny bit directly after eating but not normally
Will gasp for air 1-2 hrs after feeding while sleeping
May cough after gasping but usually passes quickly
I sit him up and sometimes he will burp and spit up
Spit up is chalky so I think partially digested
Baby seems happy and not in pain
Breathing sometimes sounds gurgly or congested when this happens

The part that worries me is him kind of choking in his sleep. It doesn't even wake him usually, though

Have an appt with our ped tomorrow