Very scary tinybaba. Did A&E actually do anything to make her better, or did she just stop by herself? Was her screaming the only reaction, or were there other symptoms too (eg rash, wheezing). Milk intolerance (or allergy) is surprisingly common, though it could equally well be the gluten from the flour. You didn't do anything wrong in offering these foods from 6 months btw - in most circumstances this is fine, and you obv had no reason to suspect she would have a problem with them.
The good news is that if it is a CMP (cows milk protein - this is what causes the problem for children rather than the lactose) intolerance then she will more than likely outgrow it within a few years (around 80% do so before school age).
The bad news obv is that she will need to avoid the offending food until then, which means that you will need to label check everything, as milk is a hidden ingredient in so many things. Generally you would be advised not to offer the food again until she is a year old, and then offer a small amount and wait to see if she reacts before offering any more (and there is an order to offer milk products in, starting with things like yoghurt and butter then moving on to cheese and cooked milk, leaving raw milk until last).
Of course you will need to establish for certain whether it's the milk or the gluten that is the problem. Statistically milk is the more likely, so I would offer a small amount of gluten again in a couple of weeks and see what happens (this is what I would do, but obv you must make your own decision about whether to offer either food type).
Dairy actually passes through in a milder form in the breast milk of many women, and constipation can be a symptom of milk intolerance (as can diarrhoea (sp), which affected both of mine), so you may choose to go dairy free yourself for a few weeks to see if it makes any difference to her bowel habits. It takes around 2 weeks to clear completely from your and her systems. It takes a little getting used to, but really isn't that bad.
Hmm mentions avoiding soya, and that is because between 30 and 40% of children with a milk problem also have a problem with soya, and so if you substitute a lot of soya into your diets then she will still be poorly, and you may conclude from that that milk isn't the problem, when in fact it still could be. Exposure to a lot of soya can also trigger a soya intolerance where there wasn't one before. Both rice and oat milk are available in most supermarkets these days, as well as health food shops, so go for one of those instead, making sure that you buy a version with added calcium. (I opt for Rice Dream and Oatly, and personally think that provomel rice milk is the work of the devil). There has been some recent press about low levels of arsenic in rice milk. If you have read this and are worried about it (I am not) then stick with oat milk.
The method of weaning that you choose, be it purees or blw, will make no difference to any allergies, so you may like to point this out to interfering well meaning relatives.