Small painful ball shaped lump- inside penis

Patient: I have a small ball shaped lump under the head of my penis inside the shaft. I can move it around a little bit. I’ve noticed it years ago, but its been painful a few times especially today. Any idea what it can be?

Symptoms: Painful only a few times when erect and during sexual activities and/or masturbating.

Doctor: There is a gland called Bulbo – cavernous gland around proximal / middle of the penile shaft. If it is inside the head of penis. It needs doctor’s examination and if needed evaluation.