Hydrocele is common in newborns and usually disappears without treatment within the first year. When it doesn’t disappear spontaneously, surgery may be required otherwise it could cause hernia.
It is a relatively minor surgery whereby they drain the fluid.

I have no personal experience of this, but it might be worth asking your GP if there is a support group in your area.

Wow, you took a long time to notice it. I noticed my sons when he was still in nappies. It got bigger as the day went on. They operated on it when he was about 2 1/2. No issues whatsoever, he was racing round the playroom within hours of the op. Tiny scars

Sorry can’t help you with advice but while you are waiting you can prepare list of questions and worries to talk with doctors

Yes, my son was diagnosed with this as a toddler. Same symptoms, and the ‘swelling’ increased during the day and went away overnight.
Surgery was smooth, and these days we have a laugh (he is now 8) at the fact he had ‘giant balls’ as a baby.

Don’t worry too much. Hydrocoeles are most of the time harmless and do not require any specific treatment unless they cause symptoms. I’ve seen them by elderly men when I worked as a nurse.

My son is now 17 but had the same condition when he was in year one. They operated and fixed it with no great dramas and he doesn’t even remember anything about it.