What mistakes? I trusted a Brit. Thats it, he told us that the plants were safe, he gave it all the big one about your plants, so I trusted him, the only mistake I made was trusting a Brit.
You trusted a complete stranger that you met in a pub to give you advice on the edibility of a plant you'd never come across before? As far as mistakes go that's quite a big one.
And as far as I can tell, you were lucky there. The information he gave you was right - Wood Sorrell
is edible. I just don't think the guy expected you to add it in large quantities to every meal you ate over the following few days.
If someone told you that pistachio's/ oranges/ prunes/ tomato's were edible would you eat them?
Of course you would. But you wouldn't eat so many that they gave you stomach cramps and diarrhea - something that all of those foods can easily do.
And I can't believe you didn't tell the Doc about the wood sorrel or how much of it you'd eaten. You went to see the doctor with a stomach problem and didn't tell him that you'd been eating wild food recently? Even though you knew there was a very high probability of that being what caused it
I'm glad you're feeling better after your ordeal and it didn't cause you any major problems, but please don't turn this into a whinge about the 'stupid bloody Brit' who fed you poisonous plants.