I suffered from some pretty intense health anxiety, and could literally manufacture/manifest physical symptoms at times when I really obsessed about certain things. Headaches became brain tumors. Forgetting someone's name became Alzheimer's. Dizzy spells became strokes. And Dr. Google helped me all the way along :-)
Obviously having real physical symptoms checked is the right thing to do, bit don't underestimate the power of your own mind. Have you ever spoken to anyone about the possibility of anxiety?