Jessyem88,
sounds like youre describing the symptoms of arrhythmias. An arrhythmia is any disorder of heart rate or rhythm. Arrhythmias are caused by a disruption of the normal electrical conduction system of the heart. There can be a problem in the heart muscle itself, causing it to respond differently. Arrhythmias include tachycardias (the heartbeat is too fast), bradycardias (the heartbeat is too slow), and "true" arrhythmias (a disturbed rhythm).
People at higher risk for arrhythmias and complications from arrhythmias include the following: those who have a history of cardiac conditions such as coronary artery disease or heart valve disorders and also, those with imbalances of blood chemistries. Arrhythmias can also be caused by some substances or drugs. These include beta blockers, psychotropics, sympathomimetics, caffeine, amphetamines, and cocaine. Sometimes antiarrhythmic medications that are prescribed to treat one type of arrhythmia can actually cause another type of arrhythmia. Do you have any of these risk factors?
The symptoms of arrhythmias include: sensation of feeling the heart beat (palpitations), fainting, light-headedness, dizziness, chest pain, shortness of breath, changes in the rate, rhythm, or pattern of the pulse, paleness, temporarily absent breathing. From what you have described it sounds like some of these symptoms apply. Are you experiencing any other of these symptoms?
Please let me know if this information has helped you in anyway.