I am guessing if your new bearing came factory prelubed that the grease
may have been dark in color and that you may not have a problem, other
than that now you have two different types of grease in that bearing.

Here is what I would do:  remove the bearing - it just comes right out
- scoop out any loose grease with your fingertip.  Wash the bearing in
a small can of gasoline until it has no grease at all in it.  Let it
dry thoroughly and inspect it - any pits?  scoring?  Blue color?  if
all answers are no repack with the grease you used for all the others
and reinstall, drive happy.

If yes to any, you will have to remove the rotor to drive out the
bearing race.  It is not recommended to mix bearings and races; I've
seen it done with no ill effects but it's not that hard to remove the
rotor,  just remove the caliper, hang it out of the way, and slide the
rotor off.  Drive the inner bearing out through the rear of the rotor
with a brass drift, that will pop the inner seal off without damage and
you will likely be able to reuse it.  Now you can drive the inner race
out and replace it.

BTW I have a cheap plastic bearing packer that works with a grease gun,
it is a huge timesaver for jobs like this.  I keep my grease gun loaded
with Mobil 1 chassis grease, that is good for both wheel bearings and
tie rods so I only need one gun.  Doesn't hurt that my rear axle
(Studebaker Dana 44) has threaded holes for a Zerk fitting so you can
touch up the grease for the wheel bearings without any disassembly -
gotta love old, user-friendly cars.

good luck,

nate