Glad to hear your little man is doing better now. My DS had his first gastro bug a few weeks a go now and like yours didn't really eat anything for the 5 days he was sick. It took him a good week to start eating solids normally again. I wouldn't worry too much at this stage, it might take him a week or two to get back to normal and being his age solids really aren't too important, as long as he getting lots of bm he'll be fine.