What could it be? :(

Right, over the bank holiday wkend I ate between 1700 - 2000 calories for 3 days, did no exercise and had a cake or two and wasnt eating too healthy.. When I came back home I weighed myself and I had gone from 173 to 171.4!! I was well pleased, as you can imagine... But two days ago I went back to my healthy eating and exercising and i've gone back to 174!!  I ate 1200 tuesday, ate 1700 yesturday and am on 1400 calories today... how come I lost nearly 2lbs and then shot back up once I went back to eating healthy and exercising?

Please help, im so disheartened

oh, also I ate breakfast over the bank holiday wkend... I dont usually eat breakfast could that have something to do with it?

Im in the same situation it came to the bank holiday and I went a bit mad? I put it down to increased sodium and have started to see the effect of drinking more water to get back down from 180lb to 175lb again  tho I think i maybe did gain 1lb in weight from all the crap I ate.

I think it depends on the sort of food you ate really, I know it can be disheartening im living it right now the main this is I had fun over the bank holiday and caught up with some old friends. 

Breakfast is one of the best things for you usually... i'm not sure if it contributed in this situation, but I would highly recommend eating at least 150 calories before you head out in the mornings.

Give it a few days.  It's possible that just like me you ate some food loaded with sodium and you gained some water weight.  I wish I had just added 2 pounds...I gained the 10 pounds that I had lost in a month overnight but now 4 days later I am back down 8 pounds and it's still coming off.  (I also probably got dehydrated from working outside all weekend.) Drink some water and give it time.

thank you for the replies.. Im glad im not alone with this and other people have the same problem, was starting to think something was wrong with me lol thank u once again :)

Maybe you ate all day and kept your metabolism at a steady rate, where during the week you might get hungry and don't have time or your trying to cut calories and then when you do eat your body stores all that fat. or maybe its from the exercising maybe your building muscle , it weighs more then fat.