This is not right, and should be the subject of a letter of complaint to the CEO of the responsible trust and the CQC. Is it possible they are breaking the requirements of the new GDPR by allowing your condition and treatment data to be revealed to any casual audience?
Yes, people shouldn't go to A&E but they do (were there no appointments at their local surgery - we don't know?) but there is a duty to maintain patient privacy. When to go to A&E or your local pharmacy is a matter of education. Even then, pharmacists are not doctors.
In our trust, patients are triaged in a private room and asked to then sit in the waiting room again until called. It doesn't take much effort to provide these facilities. The workflow is well organised, and very professional.
As for getting changed in a corridor with drunks about! This is quite shocking. and the person was absolutely right to refuse. This lack of thought for patient comfort and care demonstrates a lack of empathy or emotional intelligence, and a decline in professional standards. What's next? We don't need gloves for a few procedures? Or curtains in A&E? They are supposed to put you the patient first, not themselves.
It might be worth having a look at the Francis Report for Mid Staffs, which recommends that this type of thing should be brought to the attention of the trust and DEALT WITH, as it is symptomatic of decline and poor leadership.
webarchive.nationalarchives.gov.uk/20150407084231/http://www.midstaffspublicinquiry.com/report
Always complain (otherwise how do they learn?), and always ask what is being done about it, and by when.
As a lay person in a team I inspect a type of hospital department and the associated procedures. There is no accreditation unless privacy arrangements are up to scratch.
Having said that, NHS staff are under pressure, underpaid, and the whole thing is underfunded. The majority are totally dedicated and caring of their patients. But this sort of thing must be stopped as soon as it appears.
So complain, formally, and in writing. Good luck.