Determining quackery often involves intuition. Does your gut tell you something is not right? Has s/he talked to you in an inappropriate way? Has s/he touched you in a way that makes you uncomfortable? Does s/he argue with you about your issues instead of leading you to explore them? These and more questions will help you determine if your psychiatrist is indeed a quack.
Your psychiatrist may not be a 'quack', having gone to medical school for many years and jumped through many hoops to get his/her degree. S/he may not be the right person for you, however. Patient and psychologist do not always 'fit' together for several reasons. Personality conflicts, misunderstandings, transference and counter-transference, and more can cause a problem between a patient and his/her psychiatrist. What may feel like 'quackery' may actually just be a bad 'fit' which should indicate it is time to look for another psychiatrist.
While 'quacks' in the form of those who have fraudulent degrees or have been abusive in some way exist, his/her credentials can be checked fairly easily. Anytime you use a professional, wisdom says check their references.' You can also talk to others who have used the same psychologist to find out if you are the only one experiencing problems. If your psychiatrist suggests something that sends off warning bells in your head, it's probably a good idea to check it out or to seek a second opinion. The majority of those who seek psychiatric or psychological care are not psychotic, there are merely neurotics looking for healing from life's blows. You should trust your own judgment, and get out if you think a problem exists.
On the other hand, if the problem is a bad 'fit, between you and your psychiatrist, it can be handled in several ways. First one would talk to the psychiatrist about the issue. Misunderstandings abound among human beings, even those with psychiatric degrees, and simply talking about it can often bring resolution. If this doesn't work, you must decide if you can live with things as they are or not. If not, you need to move on and find another psychiatrist that can meet you where you are emotionally and help you in your process of seeking mental health. Your current psychiatrist may be able to help you by referring you to someone who will better meet your specific needs.
Regardless of the problem, you need to trust your instincts and find the best place for you to have your needs met. Sometimes people just cannot connect in a healthy way, and when this happens, especially in a mental health setting; it's time to move on. Resolving your mental health issues may be important, but working with someone you do not trust, or who makes you feel uncomfortable will not promote healing. So, check him/her out, trust yourself, and make other plans if you feel you cannot work with your current psychiatrist.