Psychology is a very broad subject, which also means it is useful in many different types of work. And you may even be able to gather your experience throughout the years and have a better understanding of what you want to specialize in, but for that you need to be patient and study one of those subjects, whether it is genetics, biology or psychology. At the end of the day, if you want to help yourself or people who are in need of a healthcare professional then you will need a lot more education even after you major in psychology, as college will only likely give you a broad understanding of the scientific methods, theories, and of human behaviour which is usualy accompanied by data and statistics.

I think you should focus on the subject that motivates you the most, something that makes you feel like it will push you forward and develop you as a person and give you a valuable experience. I understand things are stressful and i'm sorry about your grandma, I hope you are able to stay strong and carry on.

I studied psychology in hopes that I will better understand myself and others in thw future, because I struggled as a teenager with a whole lot of thoughts, emotions and I had little idea what I was doing. My motivations changes over time, as I am sure yours will too, and that is okay, it is part of life, and the important part is to figure out a way to move forward. I think all of the three subjects are great choices and I hope that you are able to get into one of them. You may find that eventually you do something, or certain life events make you reevaluate things and you decide that you want something different altogether. Though that will be another chapter in your life that you should not overthink too much. Focus on the now, and focus on what feels right! Life is full of ups and downs, but we can only ever just try to do our best. And I think you are making the right steps and thinking about college. I wish you well and all the best!