For the last 2 days i'm feeling nauseous evrytime i eat at least for one or 2 hours after eating. i have ibs for more than 30 years but it's been a long time i don't have continuous episodes like this. can it be my ibs?

While nausea after eating can occur with IBS, I look for other causes if there's no associated abdominal bloating,cramping,etc. Since it's been only 2 days, I'd eat only bland,soft foods but you could try drinking flat ginger ale and/or take some dramamine 1/2 hour before eating to prevent nausea. Development of diarrhea could be from IBS flareup,viral infection or minor food poisoning. ? Call MD