new brakes but still soft

I just put new brake pads and rotors on the front of my '98 GPGT. I got in and pressed the brake pedal till it stiffened up. After starting the motor and getting ready to go I put my foot on the brake pedal and it went to the floor. The fluid level is still where it should be. Do I need to bleed them?
I do not see any fluid anywhere.

You shouldnt have to bleed them. Did you pump it a few times with it running to see if it stiffens up? Take it for a spin. Sometimes it "feels soft" and then it actually stops really good.

The only thing I can think of is if you compressed the brake caliper pistons fully into the housings, the first stroke of the pedal would bring them back out and be a soft stroke.

The vac boost allowed more piston pressure which then realigned the "equalizing" feature of the calipers on the 2nd stroke with the engine running, and it would be a soft stroke.

Bottom line is if the pedal feels firm now you are good. If it is still soft you need to bleed. Bleeding isn't a bad thing, should be done about every 5 years IMHO as the brake fluid attracts water like bees to sugar. Each piston should be bled back to clean, golden fluid which would be poured fresh into the master cylinder.