Is it just a baby thing or is it just my son.

My son as any other babies cries when he’s hungry and wants for milk, but recently he’s crying as if I haven’t gave him milk for a few days but I just had given him milk 2 hours ago. He’s getting super impatient and cries as if he was beaten. It’s super stressful seeing him cry like that and waiting for the breastmilk to warm up.