We've all been there, done that with things not being the size we expected. You might want to check the Free Videos section, the button is at the top of the page. There are lots of useful videos there covering all the basics including gauge.
Cheating is an option. . . . Cheaters never win and winners never cheat, but smart knitters who want to retain an iota of sanity do, cheerfully. ~~Kory Stamper