I'm not very far in the game --well according to patrick, at least. I've heard conflicting info with him saying it's a 10 hour game.

Anyway, I'm at the part where you gain access to the wind tunnels that allow you to transport between areas and just noticed that I missed some rooms that were before the area where you're quarantined.

My question is, will I be able to backtrack to get back to that area and finish those rooms, or should I just restart (less than an hour in, so that ain't a huge problem).

Not that I have to do those rooms, but I like to experience everything in these kinds of games

There is only one point right near the end where you cant backtrack which i will mention below. As you get further into the game you will be able to go back.

It's not 10 hours. I got through it in 4 hours, solving all the puzzles too.

Yeah, whoever told Patrick he was only half way was either a liar really terrible at the puzzles.