@Alida31
Sorry to read of your unfortunate experience.
Did you agree with the Host to check in at the time you arrived?
If they knew you had a medical condition that's unacceptable to treat you so disrespectfully.
It's a basic Human Right to be treated with respect & dignity.
You may like to reach out to @Laura_C who is Head of Customer Services via PM system on here (she's also an Australian) & discuss with her your concerns to see if there's a positive way forward.
I'm not qualified re payments of expenses incurred in your situation however it sounds like you have had a challenging time.
Maybe you can claim those losses back through your Travel Insurance.
Always take a phone charger or powerbank with you if you can to keep your phone charged.
Meanwhile take care & enjoy your time with your friends & holiday in London.
All the Best
If you are near the London offices of ABB CC you may like to pop in & see those who work in Admin on here in CC.
It can be daunting traveling abroad & not been familiar with the area and distances.