What is causing such an attitude?

First off, I just started my first semester of college. To give a brief introduction, I used to be a very academically strong student in high school, graduating 3rd. of my graduating class. During the end of my junior year of high school, going through my senior year, and now in college. I have realized that my focus in school and concentration was gradually declining more and more as time progressed. My academic performance was deteriorating; to say the least I feel as though my entire brain has been deteriorating and do not know what is going on. My entire life I dreamed of going to college and then to either medical or dental school. Now, after entering college, no matter how many hours I spend studying it seems as though the information I am reading is not sinking in and I get really frustrated. During the test, I get so tense and nervous that I when I look at the question I cannot come up with the answer and blank you or have a hard time thinking about the answer. Once the exam is over and all the papers are collected, I then realize that I indeed did know the answers to the questions that I missed. As the days progress I am getting more stressed as the days progress. At times I think too much about the future and wonder what I will do with my life with such poor college performance and academic difficulty this early on in my college career. I recently began to have doubts about my dream of becoming a doctor and through of alternate lower paying careers that take the least time to attain such as a police officer and an EMT. I also thought about nursing or dental hygiene, the list goes on...I sometimes am so discouraged that I have thoughts about dropping college all together. Also, my negative attitude is effecting other aspects of my academic performance such as not caring as much in class, thinking that I will do poorly anyway again, why even bother caring anyway. I feel as though I am metamorphosing into a new being, one that is self destructive, one that is a complete opposite of what I had been in high school. What is happening with me? (I met with my doctor, nd still waiting for the test results back.)
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My first thought was that perhaps you are not in the right field of study. You may also have a bit of ADD, although not likely. Perhaps the anxiety of college is getting to you. What do you do as a hobby, is it only study time for you? Perhaps a break would be needed from school. Many times, students that succeed very well in high school have extremely high expectations for themselves and from others around him. I think you may just need to re-evaluate what it is you really want as a career....You say you get discouraged when you think of nursing, EMT etc. There is nothing wrong with those careers. In fact, you may be better off to do a course that is not as long (such as a dental hygienist) and then after working in the field for a bit, re-consider if you like it enough to go back to school and become a dentist. Good luck with your decisions.
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