Over a year ago I started experiencing fatigue, heart flutters, weight loss?

Hello, I am a 27 year old female. Over a year ago I started experiencing fatigue, heart flutters, weight loss and a few other small symptoms that lead me to be concerned about my health. I was given a test for Addison’s disease which came back twice as inconclusive and was told it must be stress. I then spent a year with a psychologist going weekly and attending coping skills courses. Some symptoms lessoned. I honestly lost faith in going to the doctor and hadn’t been in over a year until I developed a UTI, which I have been treating with antibiotics for close to 3 months now. I just finished my 4th type yesterday and it is already showing symptoms again. I also found a small hard lump at the bottom of my right breast that causes me no pain and moves. I just received blood work back today that says I am now anemic. I have an appointment Wednesday and I would like to know what type of tests do I ask for. There is an underlying issue that is causing my weight loss, poor immune system and these issues and I feel that they are only treating the symptoms instead of taking me seriously and looking for a cause. Please help me I am lost and tired of this stuggle and I have no medical background to help me figure this out on my own.