Thephrase"HappyBirthday"iscommonlyusedtoexpresswellwishesonsomeone'sbirthdayinEnglish.Tospecifyitisyourownbirthday,youcansay"HappyBirthdaytome"or"It'smybirthday".
The phrase "Happy Birthday" is commonly used to express well wishes on someone's birthday in English. To specify it is your own birthday, you can say "Happy Birthday to me" or "It's my birthday".