What a pain... I have just experienced a similar thing after losing a bit while on holidays, but eating different foods. 2 weeks post hols and back into my standard meal / exercise plan ... a big fat plateau when I should have dropped at least 1kg... Who knows?!!? I was wondering if it's because I allowed processed carbs and alcohol back into my system, may take a little while to clear out again maybe? Hope your body figures it out and gets back with the program soon...