E.C.
Your son is being a normal toddler - it's actually a normal and common developmental stage to go from "eating whatever mom or dad puts in front of me" to "refusing something I wolfed down just last week" (Nutritionist Ellyn Satter describes this phenomenon and how to address it much better than I could in her book "Child of mine, Feeding with Love and Good Sense" - basically she says to keep offering healthy foods, expect that it can take several tries for your child to even let you place an item in front of him and a few more tries for him to actually taste it -and he'll eventually come around. Good luck!