You probably wore them out. Pelvic floor muscles wear out super fast on men because we've never had to use them as actively as women do. Lower your sets a bit if you need to - while the number of sets is important, it's more important to just be consistent in doing them at all.

For me, I know my pelvic floor is done pretty quickly. I incorporate kegels into all my normal exercises, like weight lifting and squats and kettlebell swings, so I wear them out pretty fast - usually about 30-50 reps of those things at most and they are toast for several hours.

But, because I incorporate them into other exercises, I'm pretty sure I can crush a full sized truck with those muscles at this point 😀