its normal.
Breastfeeding is arduous. And it is all the time. This is normal.
Especially during growth-spurts and cluster-feeding, which is normal and common in babies.
Both my kids did that too, they had GINORMOUS appetites and I just fed on-demand. And 24/7 day and night.
If you give him Formula, in lieu of breast, then your breastmilk supply will get affected... so bear that in mind.
AND, some babies will then ONLY want a bottle (and reject breast), because sucking from a bottle is much easier, than from a breast. It requires 2 different 'techniques' to drink from a breast v.s. a bottle. Bottles are just by gravity. My son was like that.... after awhile. Though I still would nurse him.
Your baby IS normal. This does happen.
He is only... 4 weeks old.
You need to always feed on-demand.... NOT by a "schedule." Because, each day, appetites and growth fluctuates. And you cannot "predict' the needs of a baby's intake. A baby ALWAYS will need to feed/nurse. And sometimes it is even EVERY SINGLE HOUR. My kids did that too. Cluster-feeding. And they grew like weeds and were happy and were very healthy. I just always nursed on-demand.
At 4 weeks old, you cannot make them, feed or sleep by a schedule. You need to go by your baby's cues.... and needs. It just is. Every baby is different... but all need to feed on-demand.