hi there, The very first infection can go unnoticed as it could be a small area of redness on the affected area,but as the herpes viral infection tends to recur then the most common feature on the repeated infections usually is burning or stinging on the affected areas,then they will form pink bumps which then converted into small vesicles. These vesicles dry out very quickly and form a crust and then it start to disappear within couple of days. One important thing regarding the Herpes simples viral infection is that the repeated attacks would be more or less on the same site. I hope now you can easily differentiate it from other eruptions,by the way cold sores,fever blisters and herpes simplex labilalis are all the same thing with different names.