how long can I stretch out feedings

Hello my baby is now 7 weeks old. I usually feed him every  2 1/2 hours and he drinks. But this week he wil barely drink. I feel like I'm spending hours "trying" to get him to drink should I stretch out feedings maybe that'll get him hungry. If so How long can I stretch them out ? Can I go 3 -4 hours ?  He barely seems hungry this week and I'm always engorged. I would pump but he doesn't take a bottle so I'm kind of wondering what I'll do with the milk.  He is exclusively breastfed .