Some schools, notably princeton and upenn “recommend” me to send all my scores. However, my scores went up drastically and I dont feel like I want to send my old scores in. Would using score choice decrease my chances of getting in?
No
Using score choice in that situation is allowed and will not be considered against you. Just be aware that many high schools put all your scores on official transcripts sent to colleges, so you should check what your high school does since using score choice with College Board may not be enough to avoid Penn’s or Princeton’s learning of the scores.