Bike Workout - Short FTP Intervals

I wasn't feeling great today, but I got up to do the workout anyway, knowing I'd probably cut it short. I did cut it short (skipped the last 15 minutes of 85% FTP), but I managed to do the entire main set of FTP intervals. Like Tuesday, this hurt today. I wonder if I'm just really fatigued.

Workout Summary

FTP Interval 1:
 Duration:   11:58
 Work:       192 kJ
 TSS:        21.1 (intensity factor 1.027)
 Norm Power: 267
 VI:         1

FTP Interval 2:
 Duration:   11:58
 Work:       190 kJ
 TSS:        20.7 (intensity factor 1.018)
 Norm Power: 265
 VI:         1

Entire workout (200 watts):
 Duration:   45:06
 Work:       540 kJ
 TSS:        58.8 (intensity factor 0.885)
 Norm Power: 230
 VI:         1.15