I hope that entities are real but cant state that for a fact.
The chances are that “the witch” lodged some doggie program into your subconscious and it began playing. The more attention that you give you curse the more real it will become. Alternatively meditate on the moment that it began and things that it caused since, and try to track it back to it’s source (it’s with in you if its affecting you) and try to identify and delete it good luck.