5 months po. question about digestive problems and feeling unwell

I’m 5 months po and for the last month have been doing well thanks to starting on digestive enzymes and probiotics. I know what foods to avoid and do well with those that don’t upset me. But now and then I slip up or try something new and it doesn’t always agree with me. I then get diarhoea, nausea, gas and bloating. Usually the day after and sometimes lasting two or three days.
My question is this: When I get this reaction I also feel unwell as though I’m coming down with flu, aching joints and muscles and a thick head. It only lasts for the time of the upset though.
Does anyone else experience this and if so, do you know why this happens?

yes, i am 13 months post op and still have the same. i also take probiotics and still Ranitidine for my digestion. but i am perimenopausal and the aching joints, thick head and this type of symptom for me are down to hormones. Just wanted to mention this in case you are 35+ it could the sane for you…take care.

Thank you. I’m past the perimenopause phase so I dont suppose it’s that.
just wonder why it only happens when my stomach reacts badly to the wrong food.