1) the testicular pain may or may not go away on its own. you have nerve compression/irritation in the inguinal area. you can try some core strengthening exercises, but they are no guarantee
2) same as #1, surgery usually relieves the pain, but again, no guarantees - which you will hear from any surgery you see, that he offers no guarantees
3) possible side effects are PHPS - post herniorraphy pain syndrome, also called inguinodynia or inguinal neuralgia. other side effects may be localized numbness at the immediate surgical site
4) most swelling will go away after surgery following 2-8 weeks of healing, but again, if you ask these questions to a surgery, he will not guarantee anything.
the bulk of surgeons that do inguinal hernias will gloss over the surgery and make you believe it is a routine procedure that is done everyday. yes, this type of surgery is done everyday, but there is nothing routine about it. if you feel that you absolutely must get it repaired, increase your odds of a successful outcome by going to a dedicated hernia specialist and not just a general surgeon.