Rubi,   There are a multitude of factors that could contribute to changes in your period.  An extensively long period causing symptoms is reason enough to discuss this with your doctor.  Because of the long period, your blood count, or hemoglobin, may have dropped.  This can be determined with a simple blood test.  A drop in hemoglobin can certainly lead to fatigue and feeling faint.  However, your physician can best determine the cause of these symptoms.  It could also cause your heart to race since your body is trying to compensate for having a lower blood count.  Typical symptoms of a heart attack include crushing chest pain, pain over the left arm and jaw, nausea, sweating, and shortness of breath. Your doctor also best determine if you are going through menopause.   Hope this helps, HealthSupport