How should I deal with very negative feedback from some students?
Could I get some suggestion on how do I manage in such time? Is it normal for a early-age academia?


No, this is common for academics of any age. Anonymous evaluations are notoriously a valve for students to express their dissatisfaction without having to be reflective, fair, or even truthful about it. If you ask for anonymous feedback, you will need to be prepared for things that you don't want to hear. This can include very harsh judgments of your teaching quality, ad hominem attacks, or even tangentially (if at all) teaching-related comments to your person, your appearance, etc. Browsing Ratemyprof will give you a good idea what kind of statements students are willing to utter about their professors.

How you "manage" is by keeping in mind that (a) what you read is likely not the opinion of the silent majority of students, (b) that even the students that actually post hurtful feedback will often not really feel like this about you, but rather be frustrated because of a bad grade, a bad experience with your school in general, or just a difficult time in their life, and that (c) in reality, most teachers get a wide range of feedback from very bad to very good.

Also note that especially in smaller classes there can be tremendous differences between years, so having a bad evaluation in one year can still lead to a better evaluation in the following. Further, I have taken to basically ignore any feedback that has been mentioned only once or twice, and only start to take a specific complaint serious if it becomes a pattern.

TL;DR: In short, you will need to learn to not take the feedback personally.