If you still have the same stitch count I can think of a couple things. My guess is probably a combination of the two. Are you following a pattern? If so can you provide a name and link? Don’t post the pattern in the forum.
~Possibly your cast on is too tight so everything that comes after will be wider. What cast on are you using?
~ Sometimes when you first pick up your knitting you start out tighter, but as you relax and get into the rhythm of it your knitting gets looser.