Hi I.,
I"m so sorry this is so stressful. And I understand. How could it not be?! I have to say, though, having done some research on picky eating, I believe your pediatrician is correct. Here's a link to a blog post I wrote on picky eating that explains some of the research and why I support your ped's sentiment:
http://www.chowmama.com/2009/04/15/veggies-to-hide-or-not...
there's more on my blog--but i don't want to overwhelm you. not trying to promote, but just to say that i've done quite a bit of thinking about this! (not to mention i've gone through it!)
think about what you're most worried about--is that your son isn't getting enough food? enough nutrients/veggies? that he's hungry? this might help you focus your efforts and filter the advice that will come in (b/c everyone-- like me! :-) -- has something to say, but that doesn't mean it's all right for you!).
if it's veggies and nutrients your worried about, you can try looking into the hiding veggies approach. my post makes very clear that i'm not a proponent, but it's an option a lot of parents choose and feel good about.
it does sound like there aren't even that many things your son will eat that could even serve as a vehicle for hiding veggies, though, so maybe it's a more general concern that he's not getting enough. rest assured: you will NOT starve your son!! PROMISE! keep serving a variety of things--trust that he'll eat what he needs (and he needs less than you think).
the bottom line is that if mealtime becomes so stressful for you, it will also become stressful for your son. that'll just work against the development of his healthy eating habits and your sanity! so, though you think it's not possible, find a way to give yourself a break knowing that you're open to trying things out. if they don't work, they don't work. keeping mealtime as stress-free as possible is the best thing you can do during what is surely a phase.
hope this is helpful and that you all enjoy dinner tonight--however it looks, whatever it is!
S.
www.chowmama.com