Is this normal with my wisdom tooth extraction?

I had all 4 of my wisdom teeth taken out 3 days ago. And one of the bottom ones had gotten food stuck in the hole. I'm not sure whether or not I got it out. But now it's been throbbing and causing me some discomfort, no severe pain. The stitches fell out of that side and I don't know if I should be worried. The hole seems quite large, when the other side is almost closed.