Brief Answer:
List of possibilities, but most likely to be epicondylitis

Detailed Answer:
Hello ma'am and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. There are quite a few causes for pain and swelling in the elbow region, and without a physical examination I cannot really narrow down the exact cause, but I would like to list all the possible causes for your reference ma'am. They are:

+Elbow sprain: Due to injury to a ligament and require rest, ice application, the use of anti-inflammatory medications (e.g. ibuprofen, diclofenac, etc.) and elevation of the limb
+Fracture: But of course, there has to be trauma for this to take place, but the pain will be more severe than described by you ma'am
+Olecranon bursitis: Inflammation at the tip of the elbow, usually occurring from minor trauma or conditions like gout or arthritis
+Gout: Causes the swelling of the joint and is diagnosed using a blood test (to check for serum uric acid) and an x-ray of the region
+Arthritis: But this also causes reduced range of motion
+Epicondylitis: Can be medial or lateral, and in my opinion is the most likely cause as it occurs from repeated movements in a particular direction, usually occurring from either sports of a physical job. Requires a physical examination and x-ray, usually treated with the help of injections into the affected joint

I hope you find my response both helpful and informative. Please feel free to write back to me for any further clarifications, I am always here to help.

Best wishes.

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