Sorry things are so rough! I don't know if the following will help, but here goes.
Back in 2001, when I was 19, and before the docs knew I was having seizures, I started having problems similar to some of your sons. I was in college at the time, which complicated things. I would be bouncing around the halls one day, totally hyper and on top of the world, and the next day, or even later the same day, walking around in a drunken stupor, barely able to remember what class I was supposed to go to, let alone be able to obtain any information during class. My teachers thought I had ADHD, and that was why I couldn't pay attention, so I went to a doctor, and w/o really getting tested, started taking Adderall. It just made things worse, so I stopped taking it on my own. I didn't want to eat either, which started out innocently enough and then turned into anorexia and bulimia. I didn't care what anyone had to say about it, I was totally out of control and very rude. Since I was at a Christian college, this didn't go over so well, and I got asked to leave.
When I got home, I started seeing a counselor, and he talked with me about the whole multiple personality thing, too. My parents were really concerned too, b/c I wasn't being the same daughter they raised. But MPD didn't fit at all. I wasn't hearing voices, I wasn't having hallucinations, and although I'd often get confused and lose track of time, or even where I was, I always knew my name was Heidi.
I ended up going to another counselor, and started keeping a log of when these 'episodes' would happen; how I felt before and after, what I had eaten during the day (in case it had to do with low or high sugar levels), and monthly cycles(which, fortunately, your son doesn't have to worry about). We started noticing a pattern, and I even had a few of these 'episodes' while talking to her, and she helped me be able to get in to see the right docs, eventually including a neuro, after the cardiologist, gynocologist, rheumatologist, and endocrinologist all stated I had some problems that might contribute to it (heart murmur, pre-diabetes, Reynaud's phenomenon, fluctuating BP, hormon irregularities, etc.) but nothing that could really explain why each episode was so similar, with a very distinct pattern of behavior.
The good news is, five years after it all started, I'm actually doing pretty well. I'll still have auras like this sometimes, but the anti-seizure meds help control them. I can tell when I'm starting to feel 'weird', and I'll get really rude after some of these auras and petit mals end in tonic clonics, but I'm more aware of it, and I let people know that I may be rude afterwards, but don't take it personally, b/c I'll snap out of it once I take a nap. I don't lose track of time or where I am anymore. Every once in awhile, I miss thirty seconds or a minute of a conversation, but I can jump back in w/o a problem, and most people don't even realize it happened.
Right now's the hardest part, and there may be more than one thing going on, including your suggestion of some plain old regular rebellion. I know I wanted to fight the world tooth and nail when it all first started, and my parents were at wits end. But, like Mandi said, keep getting things checked out. If one docs not looking at the whole scenario and is blowing you off, search for another one. A counselor might not be a bad option either, for him or both of you. It's not an easy thing to handle, but you are by no means alone.
Good luck, and fight the good fight. We're all here with you.
"For I know the plans I have for you", says the Lord. "Plans to prosper you and not to harm you. Plans to give you Hope & a Future."