Inner Pain in Knee, Inward Movements Hurt, Walking is Funny - but Can squat 405LB+ and Deadlift 455LB+ with 0 pain?

I would appreciate if anyone can point me in right direction. I tried to go running 2 weeks ago for first time in a decade with the nice weather. You would laugh at how far and much I did but I managed to really mess up my knee. Let's just say I probably have among the top 1-5% running form among the population.

I'm not sure what it is and haven't seen a doctor / done any imaging done since I don't know if its worth it yet and due to the cost. I tried doing a bunch of googling on this but can't find anything that sounds similar. I tried researching meniscus, ACL, MCL, etc but can't to find anything. It doesn't appear to be swollen.

What could my injury be so I can research it or know what to expect and get this better?

Things that do not cause pain:

• Squats at weights of ~190KG / 405LB for reps of 5-10
• Deadlifts & Romanian Deadlifts
• Leg Curls
• Weighted Step-ups
• Manually touching or pushing my my knee in any way I can think of
• Sitting down / doing nothing / sleeping

Things that cause pain:

• Taking off my shoe on one foot with other (either shoe on my foot or side it is taken off)
• If I acted like I was going to kick a soccer ball I feel my knee would fall off
• Sitting down and straightening my leg and squeezing to lockout my knees/ my quadricep like it was a leg extension.
• Random movements walking around house (twisting and turning, but hard to recreate exactly)

Not 'pain' but annoying:

• Walking - I walked 3 miles, 5x since this happened. I notice/feel my knee is funny and not working like it should but it is not 'pain'.
• Walking sometimes feels like I added 50 years to my age? I can do it, not painful, but I feel very very slow and immobile.

Me:

• 33, male, 105KG / 230LB
• Very flat feet
• avid weightlifter 5+ a week, almost never run/ran
• Walk on average 3 miles /5KM a day on average for last 5-10 years

If it's behind and innerl Knee it could be:
Posteromedial Knee Friction Syndrome
WordPress.com

Arthritis pills might settle it and if not injection by doctor though considering its a new entity you might have to print blog note for him.

It's hard to point out the root cause without scans. Because the presentation of your knee pain is not typical. The pain could be a repercussion of pelvic bone misalignment also as there's no local swelling or inflammation. Please consult a Chiropractic, I am sure you will be helped.