Hahah yeah first route experience is such a shock for any of the 5 routes. Though I get being fuzzy on that one part if you haven't had the context of the other routes. It's actually Chase who killed Sydney. That's not a spoiler for the other routes either, you're supposed to find that out in Tj's.
I'd recommend playing Leo's next, then Carl's, then Flynn's and then Jenna.
Carl's is probably the most confusing to get through since it introduces a new idea that isn't explored in Leo's and Tj's so maybe playing Flynn's route before Carls would be better but either way I'd recommend you do Leo next and definitely end with Jenna.