KNEE PAIN AFTER RUNNING?

I just started running, I have never been a big runner, I'm a lil over Weight and i'm 190 and 5'8 tall. I'm trying to loose a little Weight and I started running but my knees are killing me BIG TIME I'm running on a treadmill this is my 5th time on it and this last time I didn't get passed 6 minuets this last time because the pain was so bad on my knees I need help!!!!!!!!!!!!!!!!!!