sensitive baby?

So my LO is 5 months old and is still very jumpy. I have a big family and so does my fiancé.. sometimes if they talk to my LO too loudly or suddenly laugh next to him he'll jump as if he's scared.. if they talk to him from behind where he can't see them he'll also be scared/jumpy. In his sleep he's sometimes jumpy as well or around loud noises.. how can I change this? Will he grow out of it? Ppl said he would get used to the noise/loud talking but he hasn't.. also when he gets his shots the next couple of days after he's extra jumpy when he sleeps any movement or sound will make his arms fly up..I feel like maybe he gets overwhelmed? Or maybe he does get scared? I feel like it's also been affecting his sleep and that maybe that's the reason why he wakes up crying from his sleep sometimes..idk what to do to change it? I know moms take their babies out all the time to shop/restaurants/etc and those places are full of ppl.. I feel like he would get overwhelmed there too.. any advice??