Hi, Priscilla ...
It looks like you are booked on the "Ultimate Western Caribbean" cruise which does not "do" the Panama Canal, as in going through the locks.
Even a one-way turn around where you only do the Gatun Locks should be a fabulous experience. I've been fortunate enough to do a complete transit (Miraflores Locks, Pedro Miguel Locks, and Gatun Locks) twice, I'd do it again in a heartbeat.
If the Canal experience is part of what you want to do, you might want to look at the sister ship, Infinity.
It's not too late to change your booking.