Training to run, over 60, need help

rufflestx

any trainers out there who can help me? I dropped 20 lbs before I started two weeks running 30 seconds then power walk 2 1/2 minutes for 20 minutes. I got up to running 1/4 mile and PW 1/4 mile for 30 minutes. Sounded like a good plan to start building up muscles to begin running. I stretch, I have power walked for 3 months almost 4 times a week, no problems. I shove in a Denise Austin CD and work on upper legs and abs 2 times a week. I know you stretch stretch stretch prior to running.
Now, I run the 1/4 mile and my right knee immediately, (stick your leg straight out and paste a clock on your knee cap), between 8 and 10 oclock (or the left bottom quadrant) gets so tender and HURTS. what can I do to build up this particular muscle?
Is this too general a question?
I am making a doc appt, but feel I might be asking the wrong person about a sports/workout problem.
thanks