Heart Beat Problem (Need immediate advise)

I remember we used to count our own heart beat by touching our lower left lung area to feel the heart beat during our school day. However I am now 26 and I can't do that any more because I don't feel the beat at rest. I can only feel that if i do some exercise.

On the other hand, I feel very tired everyday even i have at least 7 hours of sleep. I feel extremely tired and sleepy especially during 10.00a.m to 11.30a.m. My whole body is very weak during this hours until I prefer not to move around and climbing staircase. However I feel ok in the afternoon eventhough I am tired. My blood pressure has been constantly low...around 70 something.......and I suffering hazy sometime when i stand up.

I experience serious hazy when I urine after i drank a glass or two of beer. I almost fainted every time in the tiolet. sometime i really turn unconcious for a few seconds. After that, I have very abnormal heart beat for a few minutes..I have to lay down during this period so that it recover faster. Kindly advise me if this is heart problem or some other problem.