Pool size 21x13 FT - is that too small?

Hi all - I am new to the forum. I am about to break ground on a new pool, and unfortunately, I am very limited to the space I can use because we technically have a driveway running through our backyard and the city will not permit using that space for a pool.

Because of this, we can only fit in a 21ft x 13ft pool. Do you think that is an OK size or will it be too small? Does anyone have any photos of a simliar sized pool?

THANK YOU!