Thank you all so much for your responses. Especially Barb, you gave me a giggle picturing DS headbutting me to get the letdown, lol. I have a feeling that my concern over my supply might be what has been slowing down the letdown. After reading what Barb wrote about letdown being the thing that always works, I figure the increased time it's taking might be due to a combination of my stress level and also DS's frustrated sucking technique. When he just jumps on and sucks continuously the letdown happens nice and fast. But when he is frustrated he pops on and off a bit which makes the letdown take even longer.

I'm just going to persist and hope we both find a little more patience