As per the symptoms explained by you in your query, it seem that it is Bursitis
at your elbow joint. There may be a chance of infection as you have punctured it or squeezed it.
Consult you physician and he may give you a course of antibiotic, analgesic
and anti-inflammatory drugs. Later to get rid from lump you may need steroid
injection at the site or a simple excision.
Please consult you doctor for better option.