My runs have been terrible this week. Very little quality, slow, I feel tired. The fact is, I'm tired from a huge breakthrough in the mile last week. Plus, I have been having strong workouts and moderately high mileage, my body needed a rest. So I slept 10 hours last night. 7:30 PM to 5:30 AM. Yes, I went to bed before 7:30. The sun was still up. I went on a run this morning, and felt the best I have all week. I need rest and recovery despite the fact that I don't want to take it easy on myself.
You need rest and recovery too. Mentally, physically, emotionally, or from whatever is causing you stress, it is necessary to back off sometimes.
(Of course, sometimes you have to hit it pretty hard so you have something to rest and recover from...)