Had a similar pain during the same, turned out to be overly tight anterior leg muscles. Try this:

1) Pay Attention to exercise form, and other mobility aspects above and below the knee.

http://www.mobilitywod.com/2013/07/pro-episode-31-user-request-friday-live-from-the-games-patellar-tendonitis/

2) Smash your quads & hip flexors (and/or ITB & adductors if need be). Spend 8:00 per leg, twice a day.

Correct Quad Smash Technique:
http://www.youtube.com/watch?feature=player_embedded&v=5nlarY4AdQw

Barbell Quad Smash:
http://www.youtube.com/watch?feature=player_embedded&v=c57xVyqTEjw

3) Couch/wall stretch like it’s your job. I’m talking like at least 3 times per day, at 2:00 per leg (6:00 per leg / per day). This is the most important in conjunction with #1.*** If this is painful, your anterior leg is too tight.

http://www.youtube.com/watch?feature=player_embedded&v=-ZX1QMTdAC4

4) Smash and stretch your calves – make sure you have full ankle range of motion. Also, anterior tibialis: use a tennis ball, or lax ball and start to “peel” it off your tibia. Clean up the fascia right below the knee.

http://www.youtube.com/watch?feature=player_embedded&v=fCFlfgCqpK8

5) Voodoo band your high hip, mid quad, suprapellar pouch, and high calf / right below your patella. Perform squats (good form) and calf raises / stretches while in the bands for ~ 20 reps. Feed you knee joint some slack by voodooing above and below the knee.

1. http://www.youtube.com/watch?feature=player_embedded&v=-RYMV0salw8

2. http://www.youtube.com/watch?feature=player_embedded&v=JVRTnKUgARA

How To Make Your Own Voodoo Bands:

http://glennpendlay.wordpress.com/2012/02/17/got-tendonitis/