18 day Ds is exclusively breast feeding . However the last few days he keeps coughing when I hold him upright after a feed. The coughs go on for a bit. I hold him atleast 15min. He sometimes also coughs when lying down. There are no other symptoms like flu or fever , no crying etc. His coughs even wakes up other family members in other rooms. They are not mucousy it's more dry cough..but I just can't figure out what is going on. Everything else is fine - wakes to feed, nappies as usual, active wake window.