Having faith in Hashem does not mean assuming that Hashem will do everything you want him to do. Hashem is not your servant!
Having faith in Hashem means telling yourself,”I don’t know what Hashem has in store for me, but I know that everthing Hashem does is good. It may not always be pleasant or easy, but it is good”.
Ideally, a person with perfect faith will never be nervous or anxious about the future. But people like that are very hard to find. The rest of us do get nervous sometimes….