belly aches while tripping?

hello, since a while i get belly aches when i am tripping and eat something. my blotters are the same for (5) years, i kept them in the fridge in a book in their original packaging.

the trips itself are good, but if i eat for example bread, the same bread i always ate, i get belly aches, like needles in my intestines.

i am over 40 and my body already shows signs of old age... might that just be that i am to old to trip and eat?! anyone else has the same problem?