German speakers often confuse “happiness” and “luck” because in German there is one word, “Glück” for both these English words. “Glück” is a noun, the adjective is “glücklich”.
If a German speaker tells you “ich wünsche dir Glück”, they wish you happiness. If they say “ich hatte Glück“, they mean that they were lucky.
Unfortunately for German speakers, the English words “happy” and “lucky” have different meanings. “Ich bin glücklich” means “I’m happy” not “I’m lucky”. This often leads to confusion and misunderstandings.
Happiness = well-being, contentment OR a pleasurable or satisfying experience
Happy = experiencing or describing well-being and pleasure
Unhappy = not cheerful or glad
Luck = a force bringing a positive or negative outcome (good luck vs bad luck)
Lucky = having good luck
Unlucky = having bad luck
A small bon mot to conclude:
Feeling lucky = hope or optimism about an uncertain outcome. This expression is often used in gambling. There is also a Google search function “I’m feeling lucky”. This function automatically takes you to the first page of your search results.
Getting lucky = to succeed in getting someone to agree to have sex with you. (I’m hoping to get lucky tonight.)