Hi ! Even though the urine test has come out to be negative, you may be having a urinary tract infection
, or a direct infection of the genital tract causing inflammation of the testis and epididymis
the pain of which can travel to the groin and abdomen due to interrelated innervations. So you should go for a urine culture sensitivity and a culture sensitivity of the semen if need be. If both come to be inconclusive, your doctor may advise you for an emperical broad spectrum antibiotic, with an anti inflammatory drug along with proper scrotal rest and support, which will relieve you of your symptoms. However, even after relief, you are advised to go for a HIV test
as you had an unprotected sex. Wishing you an early recovery.