You are probably have a recurring heart arrhythmia
which can be harmless or harmful depending on what type it is and what symptoms it produces. If you ever lose consciousness it is not a harmless arrhythmia and it warrants a specialist consultation. The only way to tell you for sure what arrhythmia it is is by doing an electrocardiogram which will monitor the electrical activity of your heart.
Judging from your description you could just have atrial fibrillation
in the "holiday heart syndrome". This syndrome manifests itself as unusual heart beat after stressful events, binge drinking
or just dehydratation in an otherwise normal person. Remember if it truly atrial fibrillation, that is a DANGEROUS condition which can lead to the formation of blood clots
with the following embolisms.