coffee - I wouldn't worry too much about the scales at the dr. It's fairly ridiculous that the doctors weigh people in the middle of the day, after people have had breakfast or just had lunch, been drinking fluids, are dressed...etc. I always weigh myself in the buff first thing in the morning and would expect a huge variation during the day. Also one word: constipation.
ready - I know what you mean re: feeling completely off food. Do try to force yourself to eat something plain if you can, even if it's just a small amount. I ate peanut flavoured crisps for about four days running, and then pitta breads. It's difficult to start, but the hunger pangs are so awful and hopefully you will feel much better afterwards. Fingers crossed for you and your holiday!!!
beemybaby - I really think you need to be speaking to your doctor. Losing half a stone in two months is not exactly a good idea when you're pregnant. Starving yourself is a bad idea, and you won't be able to do any intense exercise either. If you are worried about your weight, your doctor should be able to point you in the direction of some helpful resources, or refer you to a dietician.