Change In my right testicle

Hi hoping for some kind advice,, I've had a swollen testicle for many years and it honestly has never bothered me till now,, I've noticed that at the top of my testicle upwards to my groin has become swollen,,, sometimes now and again I get a dull pain in my groin but this is I'd say about once or twice every couple of weeks also due to the recent swelling I find it slightly uncomfortable to wear pants, can you please recommend what I should do. Many thanks in advance.