Knee and hip pain

Question
I am a fairly new runner, and have been training for a half marathon.  I am experiencing some problems with me knees and hips.  After about 20-30 minutes of running I feel as though my legs are turning to jello, and my left knee is going to dislocate.  I feel as though my hips arent strong enough to support my legs, and my form becomes very messy.  What can I do to correct this?  I am becoming concerned because increasing my mileage is difficult because my form isnt consitent and it forces me to stop running.  

Answer
Hi Sara,

Got a few questions for you...

How many weeks have you been training?
How many miles a week?
How much time/how many miles a week do you average?

Generally speaking, building up endurance is a very gradual process. Sometimes you just have to listen to your body and ease off the mileage. It sounds to me like you might be overtraining a bit and experiencing fatigue. Are any of your pains sharp? Do they persist after you stop running?

Let me know?it will then be easier for me to offer some suggestions.
- Greg