For me it was such a nightmare.... and I regretted that I was stressing over it so much. After each session, my yield was so little (40ml atmost) and I would cry and felt depressed because I felt that I wasn't providing the best.
It was such a crazy emotional circle that totally threw me off track. I was lacking in sleep, tired and stressed. Thinking back, I probably looked like a crazy lady obssessing over pumps and pumping, crying and then trying again lol. I was pretty crazy about food boosters that helped increase milk supply.
I snapped out of it about 2/3 weeks and started giving formula instead and I felt better instantly.