Hugs Juls! It does get easier, believe me, the first week or so is the worst and then your body gets into the swing of it. If I was you I'd stick with it for another week and see how you feel being as you're doing so well. then if by the end of the week you still feel the same then maybe it's not the diet for you, we're all different after all and all suit different things. Don't feel like you've failed as you haven't, one of the hardest things about dieting is finding a plan that suits you and your lifestyle, once you've done that it's easier to stick with.
You're doing well on it tho so maybe you'll feel better after your body adjusts to it. Any diet is not easy, if it was none of us would be here and we'd all be skinny lol (oh I wish!). Keep your chin up hun, we're all here for you so if you're having a bad day just come on here and have a rant, there is always somebody to listen xxx