I've had this feeling frequently in the past. Many years ago, when I was just learning computer science related concepts, I would be repeatedly surprised to see

I've had this feeling frequently in the past. Many years ago, when I was just learning computer science related concepts, I would be repeatedly surprised to see solutions discussed for which I had already had an inkling. It would usually turn out that my ideas weren't really novel or perhaps weren't really workable. With more experience and education this changed, and I've had an enjoyable career problem solving problem and inventing. Inventive minds like yours will often have insights that aren't original, but over time and with more practice, some of these will be original and practical and valuable, and you will more often have the satisfaction of making important discoveries.