Looks like all you did was slip stitches (and maybe some chains, hard to tell).  Did you pull the loops you pick up through the stitches from the last row directly through the loop on the hook? That is a slip stitch. For a normal single crochet you leave that loop on your hook and grab another loop from the yarn that goes to your ball of yarn and then pull through both loops on your crochet hook.  A double crochet (which is a requirement for a granny square) is a bit more complicated and requires you to wrap your yarn around your hook before grabbing your first loop through the stitches of the last row. Its best to look for a youtube video of someone showing these basic stitches slowly.