Subjective Experience & Development (Question)

Hi Everyone! Something thats been bothering me for so long I made an account just to ask, is if our subjective experience (The way we experience things from our body) exists because of our genetic configurations (sperm/embryo/enviornment etc) or is shared when say a different sperm merges with the zygote. Basically I'm aware a different sperm is altogether a different being/consiousness but im wondering if that being's subjective experience would be my experience? Sort of like waking up as that guy had it been a different sperm. (Or would I not exist at all) I really appreciate your own ideas or answers asap 🙏