Moms who pump

So my LO Isn't taking my breast anymore and j don't want to only do formula, I want to pump. He is 7 weeks and I'm a FTM but he is pretty high needs most of the time, I can put him in his swing sometimes for a few minutes or on his play mat for a few minutes but other than that he needs to be held or he cries. How in the world can I pump if I have to be rocking or walking and holding him? Just curious, I see momma's doing amazing jobs pumping so much and I just don't see how you have time! He will only take 20 minute catnaps and I use those to go to the bathroom, shower, let the dog out, etc. Just trying to figure out if there is something I don't know about to make life easier. Thanks!