Thanks for posting your query.
Is there any history of trauma?
You should first try to get the cause of UTI and orchitis as UTI is less common in males.
You should go for ultrasound
imaging study of urinary tract
Regarding pain yes..you can give morphine
but will try other medicines which also help in reducing swelling and pain.
Anti-inflammatory NSAIDs are the preferable medicines.
You should also go for urine culture and sensitivity for better evaluation.
Taking pain killer is not a good option, try to get the reason for orchitis.
Dr. Mayank Bhargava