Thank you Jose, for the information.
This is likely to be a swollen bursa.
It can get swollen from trauma as in sports.
Sometimes there can be an inflammation or bursitis.
In that case it can be red, painful.
Other possibility is a cyst.
As it has got inflamed, I would suggest to take an examination by doctor again.
Please keep it at rest.
You can apply ice wrapped in towel.
If there is much pain, then you can take anti inflammatory medicine like motrin if you do not have contraindication.
I hope this information helps.
I will be happy to assist, if you need any clarification.
Please feel free for any follow up query.