A huge setback?

I've also posted this on the UC forum
There I was thinking things were improving, we were on holiday in Paris, the entire duration of the trip felt like I needed to go to the toilet, and had a couple of close calls.
So Wednesday we were wandering around the Louvre, I had that persistent nag in my tummy, but that had been there all week, then it happened I had a huge accident, with 60 seconds warning and unable to find a toilet. I was mortified, my other half was fantastic, but why is this happening? He'd had an upset stomach during the week too, I think it may be because of the mineral water as I had not altered my diet at all during the trip.
Why can I not hold on? Does this mean there is still inflammation? I had 2 accidents in April when my symptoms were at their worst, before my treatment started.
I don't know what else I can do, my diet is as bland as it can be. Any suggestions.
I've cried for almost 2 days straight and I am so lucky that my other half is wonderful, but I feel that I've taken a huge jump backwards. I don't want to go outside.

I took a double dose to get me home, now I'm well and truly bunged up!
I do noy usually have an issue with diarrhoea. That's why this is so upsetting.

I still do not understand why I can not hold it, I understand that the area is inflammed, but I had 2 other very urgent toilet visits earlier in the week that I managed to hold on to untill I got to the toilet.
It just felt like I had no warning and no control whatsoever. No warning spasms, just a slightly grumbly tummy all morning.