Wait, but there was another word!
You are right, if you go to the English-Hebrew dictionary and type "worry" it will, probably give you two options (or more... but these are the most useful ones!) - לדאוג and לחשוש.
But why two verbs? Is there any difference in meaning?
Well, there is - לחשוש is rather like "concerned" - it's more rational than "worried",it's not just about the feeling, it's more reasonable.
Example:
אני חוששת שזאת הפעם האחרונה שאוכל להתשתתף...
החששות שלו לא התגשמו - הכל עבר כמו שתוכנן.