Alessandra, I don't know if you do so already, but how about weighing yourself less and measuring yourself?
If you're doing lots of exercise, you'll not only be losing fat but also gaining muscle. Muscle is more dense than fat, so the scales maybe aren't shifting because of that - you'll be looking trimmer even if the scales don't show a loss.
Also, 300gr is nothing in the grand scheme of things, - could be water retention/transit/too many tolerateds throughout the week/too much dairy. I noticed you'd had a lot of chicken drumsticks/thighs, which are the fattiest chicken we are allowed also some smoked salmon and a fair bit of jelly. Sweetners can stall, salty foods can cause water retention. Also, you had a day with no lunch, which is not ideal - if you don't eat enough you won't lose weight.
Give yourself a week of no sweetner/no tolerated items and see if it makes a difference. It will make life more boring for you, but maybe your body just doesn't like artificial sweetner. Worth a try?