Don't be. Calories are just a measurement tool, like inches or ounces. They measure the energy a food or beverage provides -- from the carbohydrate, fat, protein, and alcohol it contains.
Calories are the fuel you need to work and play. You even need calories to rest and sleep! Foods and beverages vary in how many calories and nutrients they contain. When choosing what to eat and drink, it's important to get the right mix - enough nutrients, but not too many calories.