I personally had a writer's block last year, due to the death of my mother. I was 15 days without writing, because I always remembered her, and thoughts came and went.
Writer's block exists, but is not a rule. It may appear or not. This will depend on your state of stress, emotional, health problems, excessive perfectionism, fear, frustration, ingestion of alcoholic beverages, use of illicit drugs, among others.
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Don´t be afraid and good luck in your writing career!
Writer's block is pretty much not having the inspiration and drive that you had when you were writing. But it happens to all creative people, artists, musicians, photographers, film directors, etc. I get it myself also, but how I kick it away is changing my time of working, instead of in the morning, I can work in the afternoon. You can also decide to work in another place, like the library, in a secret place that only you know about, a hotel room, any other place that is not the same where you originally work. Taking a break, going for a walk, doing something else that you enjoy like working out, watching a funny film. These are some tips that can help and you can try out when you feel stuck. But don't let what others say about you getting writer's block stop you from getting published, Stephen King, the man who has published some of the most known books of our time struggled with writer's block, and I bet he still does. Honoré de Balzac found out that he got great work done in hotel rooms. So even the best and well known get writers block.
I hope this helps, and don't stop from doing what you love just because someone said you will have walls in the road. Whenever you do get a wall, get a hammer and smash through.