i would say make sure your keep your fluids up, and continue to eat healthily, if your bug goes on for more than 24 hours, then maybe see your gp
if you are vomoting/diahoreaa (i have NO IDEA how to spell that - but you know what i mean) this is especially important.
eat what you feel you want to be eating, as you will be unlikely to feel like eating crappy food - if you want to eat starchy carby food - then your body is telling you that thats what it needs. listen to your body
The current medical advice to adults with stomach upsets is to drink clear liquids during the early stages (broth or clear soup, water, water + rehydration salts) and then to introduce a selection of the following - low fat milk and yogurt; oatmeal/rice; stewed apple as the symptoms improve.
The milk and yogurt is obviously dukan friendly, as is oatbran porridge. The applesauce provides carbs (which you will need) and pectin (the stuff that makes jam solidify and which soothes the gut).
Then slowly add in the other foods of your normal diet - I suggest you stay pv until you feel well again.