Everyone experiences this and it is not limited to anyone or a specific industry. It is truly a mixture of not knowing, failure mindset, anxiety, comparison, and strategy. It is the feeling of not being good enough irrespective of what you have achieved or accomplished. Comparison of yourself to others fuels this feeling of feeling not good enough. It dampens your confidence. Practice subconsciously controlling your thoughts and place your energy into aspects like why you love your job or any hobbies you might enjoy.