You'll never be anything less than what you are, but that's a strength. Just speaking two languages well already puts you at an advantage. The experiences you have of seeing the cultures in relation to each other also gives you an edge.
Sometimes it's nice to be able to just blend in, but life is all about learning and gathering experiences and impressions, and you have a head start. It might not always be easy, but you'll learn to appreciate it.
And as long as Poland is in the EU I'd much rather have a Polish passport than an English one.