Another vote for PT! I herniated 2 lumbar discs one night about 3 years ago. Just stood up from the computer and BAM--my back shot down my leg. I cannot even describe the pain. I managed to get into bed, but I couldn't sleep for the pain. In the morning I went to the ER where they did an MRI and gave me pain meds. I was in agony.
Thankfully, my doctor recommended PT. It saved me. I went 3 times a week and practiced my "moves" religiously at home. It took me about 10 days for the initial inflammation to die down, 5 weeks until I could sit for more than 10 minutes. In fact, when I went back to work I had to lie down on the floor every 20 minutes just to stand the pain. I was in PT for about 3 months and in the end it was very successful. I didn't need cortisone shots nor surgery. Just specific exercises, rest, ice, and pain meds(mostly Tylenol.)
Good luck to your son. He's so young, I hate he herniated a disc. I completely sympathize with him--they pain is just unbelievable. Best of luck to him in his healing.