The most common intolerances to cause these symptoms are:
Wheat (pasta, bread, biscuits, cakes),
Dairy (any cow products usually including milk, cheese, yoghurt, icecream),
Potatoes( any variety, although sweet potatoes are usually OK)
Sugar (any processed or refined sugar. Natual sugar in fruit is usually ok).
If you are going to try cutting something out, you need to give it a week to clear out of your system entirely, and at least another week (preferably 3 weeks) after that, to see if you remain symptomless. A few days wont be enough.
You also need to be very strict about checking what you eat.. It is pointless cutting out wheat in bread, but eating pasta, or cutting both out, and eating biscuits. You will find they sneak wheat and potato starch into loads of things as filler. So read your labels thoroughly!
If you are serious about it, i would strongly recommend finding a copy of this book:
Food and You, Stage One, (introducing the Four Zero Experience) By Althea Haydon.
It is strict but very very good. I tried it a few years back with along with my ex, him for skin problems, me for intolerances, we were hyper vigilant, andas she said, we felt awful for about a week and a half while the toxins left the system (especially the sugar), then felt absolutely amazing. Energetic, clear headed, clear skin, no bloating.
Amazing...