Slurry with a coticule can be quite dulling, so it should only be used sparingly. If the razor was shave-ready, but just needed a touch up, I would skip the slurry step altogether. I would just try a bunch of laps with water only to bring the edge back. The number of laps depends on your coticule and how fast it cuts....But if it's just a touch-up, maybe just try 10-20 laps with just water, test it, and add more laps if necessary.

I have a feeling giving your razor as many laps as you did with slurry dulled the edge just a little, which would explain why it wasn't feeling as sharp as before. But that's nothing some laps on the coticule with just water can't fix!