That's surprising, you put a loquat seed in commercial potting soil you bought and you get a sedge come up. I thought commercial potting soils were sterilised. Obviously that one wasn't. You might have to let it grow up before you can ID it. Most sedges like lots of water. Post some more photos towards the end of the growing season.

Pls try again, your pic didn't attach.

It's rather a dark image to see clearly but it reminds me of Photinia 'Little Red Robin' which is a very small version of a much larger and popular garden plant...

Thanks for the idea, but no, there were many of them, all of them the same leaves, smooth not at all hairy, they bloomed all the same with these leaves. They were outside all the time. I once grew Ratibida columnifera from seed and even the tiniest seedlings had bipinnatifid leaves and were rough to the touch.