Is it normal to grow out a new tooth much later than normal in life?

I discovered that on one side, i am growing a new teeth that is baskcally a little bit visible. I always felt it in my mouth, but was apparently too small at the time to see it, but now i actually can. Is it normal to grow an additionally tooth when you are already 21? And should i worry about it? It doesn't seem like a big tooth and i can imagine it actually fit there, but it would feel weird since it would be more than the other side