Don't worry too much about not getting a good result at your first WI. Lots of people have to wait till the second week to have a good loss. Sometimes it takes a while for your body to catch up with the diet. This is especially true if, before you started, you had a good old nosh as you thought there'd be lean times ahead! If you want help and feedback on what your eating post a food diary. There's lots of knowledgable people on here who can tell if you're going wrong or not.
Good luck! Keep on keeping on and I bet you'll get a good result at your second WI.