Never heard of 3k reps before.
Further in reps (12k) than the target distance (10k) sounds quite unwise in your position too.
You're in effect making 3 mistakes, too long a rep, too fast a pace, and too much volume, and it's no surprise you didn't come through the session!
I'd be more keen to see you do 6x1k at CURRENT 10k pace, not desired 10k pace, with shorter recoveries. Perhaps 90secs.
Add in your tempo, slow run and easy pace running the rest of your week, and you're well away.
Edited: 17/01/2013 at 16:42