Stress is handled differently by everyone and it is important to discuss this issue with your primary care physician
. Some people are never bothered by it and others have significant physical and mental difficulties because of it. You mentioned two events that would be significant stressors in just about anyone's life. Getting married is definitely stressful and getting a promotion can be as well.
The symptoms you describe including the headaches and the body soreness might be manifestations of stress or an anxiety
syndrome. Generalized anxiety disorder is a common condition where the affected person feels an increased level of stress and anxiety in many different aspects of their lives. This is something that should be considered in your case. In addition to finding ways to cope with these stressors, we have many medications that can be effective at reducing anxiety and improving the coping mechanism. You are correct that anxiety and stress can increase the chances of a heart attack. This is highly dependent on your age, family history, diet and other factors so its hard to gauge your risk from the information above.
I suggest that you schedule an appointment with your primary care physician. You can discuss these issues with him or her and together you can determine what the best mode of treatment is best for you.