Hi,
I'm 14 and about 4 months ago i jumped into a pool that i thought was deeper than what it really was, and i landed really hard on my foot (like flat on) and got a shriek of pain in my knee. Ever since than i have not been able to straighten my knee or bend it at more than a 90 degrees angle, without pain. I have not gone to see a doctor because I didnt't think it was that big of a deal. what do u think it is and should i see a doctor about it?

My God yes!!!! You have damaged a ligament and it will only get worse if you don't ignore it further.

I would suggest you get that appt - with an orthopedic doctor.
Let them get xrays and a ct or mri to determine if you have done something to your ligament.
I know that holding you joint in a fixed position (not being able to straighten) can lead to permanent fixation. If anything - you need PT to help get your mobility and range of motion back.
Let us know what happens.
hrtofluv

i hate to sound wierd but im new at this!! So what in the world is a PT??? Sorry, im not the brightest lightbulb in the pack!!!

hey , pt mean phyiscal therapy. i take pt once a week since i have alot of leg problem. I am only 14 half year old and turn 15 in june. Best luck and hope everything go well

Physical Therapy will help you gain your range of motion back. They will give you strengthening exercises to do at home and you will get special workouts while there. It is amazing how the range of motion comes back doing the right exercises. I actually did not realize how much range of motion I had lost until I went in for the PT. They will do an evaluation of all your motions (measuring them with a ruler thing). Then after you are close to finishing your PT with everyone happy - they will do a final measuring again to provide the doctor and insurance with the "measurable" results. That's the only way they can prove that the PT worked - comparing before and after measurements.
Let us know how it goes.
hrtofluv