I'm 4.5months post bypass. The only thing of that type I was allowed after the op was Options hot choc. My provider's routine for the first two weeks after was 125ml of liquid every hour sipped over 10-15 mins, for 16hrs a day. Simple fluids - water, tea, coffee, semi-skimmed, NAS squash, very diluted fruit juice, Options hot choc, Heinz Cream of Tom soup (the chilli one was the best), smooth Muller Light (towards end of second week I added a spoonful of sieved stewed fruit made with a tiny amount of Canderel). Nothing pureed or with any kind of lumps etc until week 3.
As Frankie has said, it sounds like you dumped - this happens when we eat fats or sugars, and can also happen if we drink too much liquid too fast. Everyone is different with what % sugar they can cope with, and in time lots of us seem to be able to tolerate more. Ideally we should be looking at products with less than 5g per 100g (ie 5%). In real terms, for example, an Activia 0% fat yog is around 14% sugar, nearly three times the max we should have, especially in the early days.
I am excited for you, and am delighted to have made room for you on the losers' bench. Good luck. Trial and error for the first three months. I found it extremely challenging (esp the transition back on to solid foods), but am out the other side eating a wide range of normal foods just not much of them. i've lost 5stone in as many months (22/24 to 16/18). Good luck - you'll be fine xx