Hey Margo,
I really feel for you here. Are your health issues documented by your GP and considered a disability? If they aren't, you need to do that asap.
I spoke with ACAS myself about being let go for my migraines, and without having my migraines being legally considered a disability, there isn't anything I can do against it. I know your Ehlers-Danlos is a disability, but I don't know if they would consider your sensitivity to perfumes that without documentation.
The people who hired you at this company are as*hats. Do not pass go, do not collect £200. They lied to you in your interview, which is not your fault. They did that to me at the last two companies I've worked at. It sucks.
I completely understand the need to work, I'm in the same boat. But is the sh*t they are putting you through right now worth it? They need to be brought to task as they aren't accomodating. What's your probation period look like? What do you have to rely on? Can you go above these Muppets heads?
You will find the right company, who is great to work for and is understanding about your needs. It doesn't sound like it's these idiots. They seem to be taking your sensitivity as being something that is a mild inconvenience rather than a literal health issue.