Re: healthy vegetarian diet in a dorm?
There are some really tasty veggie "add water" soups out there from Fantastic foods that usually have a good amount of protein too, in my local store they sell for about $1.19, which isn't bad if you can grab some salad bar veggies.
I know luna bars aren't the best choice, but i keep one handy almost all the time, it's better than nothing I guess.
If you have access to a microwave, those cans of veggie chili are cheap and a great side dish to pasta. Another idea is try whole grain stuff: quinoa, aramanth are both high in protein and you cook them like rice, and whole grain breads, whole wheat spagetti, brown rice will give you more nutrition than the white stuff (although the good stuff is not often found in the dining hall). I think there are some high protein cereals out there too, maybe a kashi brand or somthing, my generic grape nuts has six grams of protein per half cup, you can buy the little boxes of soymilk that has extra protein too!
I know it's difficult, having a microwave, oven and fridge has made being vegan so much easier, there are so many choices out there now!