Thanks for posting your query.
From description it seems that you develop soft tissue injury
after fall . Large lump might be due to haematoma
formation(collection of blood).
You need an x-ray to rule out any bony injury.
I suggest you to consult an orthopaedician nearby for a detailed examination. You may get the X-ray of the area affected under his/her guidance.Beside icing and elevating it, you can take anti-inflammatory drug like motrin
to reduce pain and inflammation. Avoid putting weight and rest well.
Hope this will helps you. Feel free to ask me if you have any further queries.
Wish you good health. Take care.
Dr Saurabh Gupta.Orthopaedic Surgeon