Do you always pump the other?

75% of the time, DS (just over 3 wks old...) only drinks from one side per feeding (he usually only nurses 10-15 mins total. If I disturb him and try to give him the other mid-feeding, he sometimes will take it and sometimes won't. Oftentimes, I pump the other side. But, I'm worried that I'm creating an artificial demand by pumping too much. Then again, if I don't pump, my breast is overly full and really hard for him to drink off of next feeding (and I think I have a fast letdown meaning he gets drowned and chokes).

Thoughts?