Welcome to HCM!
After going through your question I can tell from my clinical experience that you have injured your foot and knee(during fall, the pressure transferred to knee on hitting the floor with left foot).
As you have pain, and difficulty in moving around, bending more and climbing stairs, it will be wise to see an orthopedician. Only after careful examination of the leg one can pinpoint the diagnosis and give appropriate treatment.
Had I been treating you, I would go for an x ray
knee joint, leg and foot. For pain for the time till you see a doctor, please take aceclofenac
with pantoperazole. I have seen this medicine working in such cases. It is effective in reducing the pain, inflammation and swelling. giving yourself cold
compress on the site of pain also helps.
It will be wise to avoid moving your leg too much, this will only increase the trauma.
Hope the answer is helpful for you
Feel free to ask more queries