Photos taking up WAY too much storage

Why has my photo storage doubled after updating to iOS 16.3.1?

I just updated my iPhone 13 Pro to iOS 16.3.1. Before the update my 1,500 photos were taking up around 50gb on my iPhone. After the update, my photos are all of a sudden taking up over 100gb.

It’s clear that they are not actually taking up 100gb (by looking at the 120.3 of 128) so I’m wondering if this is just a glitch. Can someone please explain if this is an issue or if I should do anything about it? Thanks.