Feeling like you are nothing can be either positive or negative.
The negative concept is when you feel you are good for nothing and basically useless. Nobody wants to feel like they are nothing or worth nothing.
The positive concept is when you understand you are truly nothing compared to Hashem: then you are truly humble and bittul (self nullified). We all need to strive to become nothing in the positive sense.
There is a saying from chassidus: “My whole life I thought I was nothing and I strove to become something: to be a somebody. Now that I have learned Chassidus I understand that I really am nothing and I strive to become a nobody (bittul)”.