I just recently had surgery for inguinal hernia on the left side. this was 4 weeks ago i have a bulge below my incision line and soreness in testicle ?

See your surgeon: Hernia surgery is very good, but not perfect. Hernias can occasionally reoccur. If you are having those symptoms, see your surgeon, who can examine you, and come up with a diagnosis and plan of treatment. Hope this helps!

Seroma vs recurrence: At 4 weeks it's possible you are just feeling the healing ridge of the repair. You may have a seroma (fluid buildup) in the hernia area , or you may have a recurrence. If the bulge disappears when you lie down, it is probably the latter. See your surgeon, of course. Testicle soreness is not uncommon. I suggest support (briefs) and patience. Good luck.