Need your opinion

Cassandra
My little guy is 2 weeks old, he was born at 34 weeks and spent 13 days in the nicu. We are nursing at home and he does well. I'm not supposed to let him go more than 3-3&1/2 hours and we give one bottle of 22 cal preemie formula a day bc they were fortifying my milk in the nicu. The situation is that he's started to get a fussy around the 2-2&1/2 hr mark, but if I feed him at that time he'll only take one side and pass out and then I pump. So I had been holding him off and letting him get a little mad so that he takes both sides and eats more. So is it better for my supply and him to let him do this snacking thing or should I keep holding him off for a bigger meal.