I suggest you check for hernia, also consult a docter at the earliest it could be because of multiple causes like fluid collection or cyst formation.
Unilateral painful enlargement of the testis can be due to chorditis,orchitis,testicular torsion,testicular cust,hydrocele or testicular tumors.
I would suggest an immediate urologist’s evaluation because conditions like testicular torsion are medical emergencies and timely medical intervention are required to save the testis.
I hope that helps.Take care and regards.
the right side of my testes is larger(times 2) than the other side.. and it's quite painful rating it to 3 out of 10.. and i can't feel in touch or see the right side of my testes. and its quite developing. i feel that it started to increase in size.