Stormy, don't worry yourself. Everyone is right, I'm sure you are just fine. Do you mind if I ask your body type? Reason being, I have had knee pain since my late teens and have had surgery once and plan to have the other knee scoped next year. And I've been through the therapy too.
Three orthos have explained to me that my body type- short with *birthin'* hips tend to make a woman's knee travel just off the path. No big deal just a fact of life for about a zillion women. It will hurt to go downstairs especially. Not so much to climb them. With exercise, I've been fine with it. And having the left one scoped fixed the problem so much. Now, I'm fine.

So, if that is the case, don't sweat it. It will be a-okay.