I am a Dr, though not a psychiatrist.
I'm sorry you feel that your treatment has been poor, but I would advise you to tell the HCP that you are recording if you feel you must do it. If there is a problem in the professional relationship, it would be better to broach this directly if you can. If you feel you can't do it alone, then I'd advise you to do so with the assistance of a patient advocate. Advocates are usually very helpful to patients in situations such as yours and I would certainly advise that you look into them as it sounds like you could benefit.
Alternatively you could ask to be treated by someone else, although I do recognise that if the issue is with a member of the crisis team this would be difficult to do as you would be limited to who is on duty. The only other way forward is to go down the formal complaint route.
I have to admit I would be unhappy about patients covertly recording our consultation- and not because of any concerns about my clinical practice. It suggests complete lack of trust in me and if a patient felt this way I'd be very concerned and would want to know so that I could attempt to rectify the situation- e.g. by explaining why I had done/said whatever had caused upset or offence, or if necessary apologising. I would also dislike the level of deceit on the patients part and I would think it would affect our relationship moving forward.
Current advice is that HCP's should not refuse immediate care to a patient due to covert recording. They should ask for a copy that can be kept with the patients medical records. Advice is also that there should be no blanket policy of subsequent transfer care to another HCP in cases of covert recording, however this can be used as the basis for doing so due to breakdown of professional relationship.
I would most likely to agree to recording if the patient asked but I have to admit being recorded would make me feel a bit odd, probably because it's not something that happens routinely and so I'm not used to it. I might worry about the recording being edited though, more with some patients than others.
My understanding is that whilst not illegal, covert recording will not be considered as part of a complaint by many trusts as evidence because there have been proven instances of the recording being edited so they are not deemed entirely reliable. As others said, I also don't think they are always admissible in court. The GMC have said they may accept them as evidence in fitness to practice hearings.