I completed masters degree in business. but after suffering with severe gastritis and weight loss, now i keep regretting for not becoming a doctor.i keep feeling docs have best life as they can treat themselves timely and be out of pain. i am angry.

Health related : Anxiety. No need to be angry specifically during these times. Doctors are considered among the worst patients due to their tendency to self diagnose. Everything else is self exercised denial that helps most of the situations. You are likely experiencing health related anxiety and establishing with a counselor and/or psychologist will definitely help. Becoming a doc may worsen your condition.