No, there is no excess-contribution penalty on this in 2017 or any other year.
Someday you will make distributions from your 401(k)s. As TurboTaxRachelW indicated, the excess amount on which you paid taxes in 2017 is not treated as after-tax basis in your 401(k)s, so you simply pay taxes again on the same money when eventually distributed as part of a regular distribution.
