BIG QUESTION. I have a week to get a flat stomach! Help!?

I'm going to Holland in a week and I am having difficulty with my weight. I had anorexia about a year ago and I've physically recovered however I feel like i'm putting on weight that i've lost. I obviously am because my mum keeps bringing up how much weight i've put on and that i'm becoming a lot more 'chunky' than I was before. Its hurting my feelings and I don't want to talk to her about it because she's not one of those kind of mums. I generally eat pretty healthily. Breakfast I have porridge, yoghurt and fruit w/ green tea and g juice. Lunch I have a bowl of bran flakes with some fruit sugar and for dinner I'll have what my parents eat eg. fish, chicken, veg, pasta. I also drink water throughout the day. I run 4-5 times a week , 3 miles a day (only in the holidays) I do hockey and also dance. I'm quite muscular, have a bony neck/chest and pretty toned legs but I'm having a problem with my stomach, hips, and the bottom half of my back. Whilst in Holland i'm going to be swimming and so many people have told me how skinny I look and I still want them to think that. I have a little pooch and I HATE it , I also have some fat on my hips which I hate as well. Is there ANY way I can get a flat stomach by next week. I'm trying to not eat as much and am having a bowl of branflakes, juice and fruit every day and nothing else. Including running and 200 situps, punches, stretching and squats. Any other tips ? I need serious help because I'm getting VERY upset and I hate myself for it. I wish I could turn back time to when I was at my thinnest but I know I can't . Please help me!