Here are a couple things to help you out:
1) You have the residual affects of a jumper's knee syndrome (or at least this limited diagnosis from the internet tells me so)
2) Osgood-schlotter's is a deformity of an enlarged tibial tuberosity that forces a greater angle of torque from the patella/quadriceps. This is only in people who have not finished growing. There is a possibility that you haven't finished growing yet, but at 25 that is slim.
3) You sound like you have tendonitis at the tibial tuberosity, or rather tendinosis at this stage. There is a small area in the tendon right now that probably appears like mucus wihin the tendon (if we were to open you up right now). This is avascular and takes a long period of time to heal. (Tendons themselves have limited vascularity, which complicates the matter further)
4) Most importantly: what to do. NO plyometrics right now. This period of complete healing will take 12 weeks minimum (or more based on how much you use it during that period). The window of re-injury will be between the 3-6 weeks after the initial injury, so be careful if you find yourself able to move without much discomfort during that period; tendons are still very fragile then.
During a tendinosis type injury, the tendon will respond best OVER A 12 WEEK PERIOD to near maximal eccentrics. What I mean by this is similar to an old article on this site describing a solution to tendonitis. What I want you to do is get on a leg extension machine and for a typical bodybuilder workout sets (2-3 X 10 - 15) have a somewhat heavy weight concentrically lifted by both legs. Pause for a moment at the top to have a comfortable transition between a two leg lift and a one leg lift. Then, after you are stable holding the weight with one leg, lower the leg on a count of 4.
(note, if you are hurting in that knee doing this on the way up on your first couple of attempts, do not do this exercise for a little bit, while doing the other exercise I describe)
The other exercises: (no big deal here)
Leg presses in a bodybuilder's set/rep scheme while keeping your tibia at a 90 degree angle to the platform.
Monster Walks: Take a thick band of tubing and tie it together in a circle whose diameter is no bigger than 12 inches. Put this around your the arches of your feet, and walk with straight legs and a wide stance forward, backward, and side-to-side with ten steps per foot.
Do this for a while to build up strength in your lower extremity. Remember that the tendon remodeling with eccentrics needs to be over a 12 week period. It will feel bad before it gets better, and you need to stick it through. Just ice the area after exercise and use this twim to not only allow your body to heal, but follow some upper body specialization scheme.
Sorry if I couldn't give you more, but, this is not only online, but I should be studying right now, so my mind is elsewhere.
Best o' luck!