I decided to flush the brake fluid on my '95 SE. When we started in on the clutch, some fluid came out of it, but then the pedal went straight to the floor with no pressure at all. Since then (overnight) the feel has come back to almost what it used to be, but still not quite right. Does anyone have any ideas what happened or if I need to do something to make it work correctly again? There is no air in the system and the reservoir is full. But I don't know if I should be driving it, although it seems to work ok.

You are OK.
The clutch when bled does just what you describe. The fluid is pushed out and the pedal WILL go to the floor.
You should do the clutch by pumping the clutch pedal many times bleeder closed, then the clutch pedal to the floor, open the bleeder and the fluid will rush out. close the bleeder and let the clutch pedal back up. repeat several times and the clutch line will be clean. The clutch line refills itself no problem on the back stroke after pushing the fluid out of the open bleeder.