This can make you feel like your heart is beating too hard or too fast, skipping a beat, or fluttering. They can be terrifying, however are rarely serious or damaging, and they normally go away on their own. They may occur due to stress and worry, or by consuming too much coffee, nicotine, or alcohol. Consult a doctor if you experience heart palpitations frequently, for longer than a few seconds, or if they are accompanied by dizziness, loss of consciousness, chest or upper body pain, nausea, excessive sweating, and shortness of breath.