What am I doing wrong?

Today I weighed myself and thought, whoopee another pound lost! And then, checked my scales against someone elses thinking it was too good to be true. Anyways, long story short I have been fooled into thinking I had lost 4 pounds in 2 weeks, when in actuality I have lost nothing :(

I'm so gutted and don't know what I'm doing wrong. I also always measure myself and there is no difference ANYWHERE!

I just recently went on to Levothyroxine so I feel much better now my thyroid isn't acting up, I'm exercising (either running or aerobics) for an hour every other day and eating  1700 cals which means 3 nice sized meals a day plus a couple of healthy snacks.

The other problem is I am in uni and am catered for but I try my best to estimate what I'm given (I know this isn't helpful but it's that best I can do without bringing scales to the dinner hall!)

Whats going on and what am I doing wrong?? Please help me :( I need some answers its getting me down!

oh and here's a great fact for you too, I lost a lot of weight with this many calories and this type of exercise just over a year ago and it worked really well and now its not working at all.... Why? ARGH!

It's really easy to underestimate portion sizes and calorie content and that could add up. Maybe you've been eating more than you think? 

really? I mean I try to be as precise as possible and I feel like I get enough energy and what I eat is generally pretty healthy with the odd slip now and then. how much would I have to underestimate to not be able to lose the weight?

Only weight yourself on one scale - scales vary.

You could come to my house and you'd get a different weight too!  I go to the doctor and their scale is different.  Weigh on your own scale-only!  Cheer up.  Besides, did you weigh at the same time both days and wore the same clothes (or nude) both times?  Had you just eaten?  Too many variables to worry about.  Weigh on your own scale; I can't say that often enough!

Weight can yo-yo daily from many factors. I have varied by 6 pounds dependant on fluid intake, time of day and other things, so don't put too much weight into daily measurments (spot the bad pun).

Add to that different scales are calibrated differently by a few pounds, and all you can really rely on is a trend rather than precise measurments.

If you are truely eating 1700 cals a day and 3ish hours of exercise a week, you WILL be loosing weight. However it takes about 3500 cals deficit to burn off a pound, so combined with the other factors above it might take a while to see a noticable consistant difference.

A better thing to look at may be general endurance (how much exercise you can do before tired). I find this improves week on week, so is a much more encouraging than measuring a yo-yo weight. As your fitness improves, so will your body shape and energy - forget about weight, being fit is where it is at.

Thanks for the encouragement people! I guess it was because I wasn't seeing any improvement measurement wise which is why I was worried but you were right about the endurance leeishere I can see a definate improvement. I'm one of those people who loves quick results maybe I just need to up my game a little bit. Thanks everyone, helpful as always

Yes, only use your own scale.  Weigh yourself once a week in the morning when you get up after going to the bathroom, and before eating or drinking anything.

Good luck!