Why is my stomach making such noises?

So I'm lying here relaxed in bed and watching Netflix. Then my stomach starts to growl. Since I thought that I was hungry because I last eaten something this morning, I made something to eat. So I ate (15 min ago) and he is still grumbling. And it slowly hurts a bit…

Would be great if someone could explain that to me

There's air in there from hasty eating!