I did my weekly weigh-in today and I've lost 4 lbs since last week. I'm not too worried about it. I have been keeping my calories between 1500-1800 this past week and I have worked out a few times. I work as a waitress so I was walking for probably 15 hours of my weekend. I think I remember hearing you lose more weight in the first week then it goes down. I've been tracking calories for a couple weeks now and I don't think I've cut back a lot from what I ate before. Are there any exceptions where it is safe to lose more than 1-2 lbs a week?

Yes. Weight loss will never be precise or linear. There have been weeks on end where I lose NOTHING, nada. Then a week will follow where I drop 4-5 pounds.

See JayEll's excellent thread that illustrates her weight loss...
http://www.3fatchicks.com/forum/showthread.php?t=161386

Any time in the first month I wouldn't worry too much about rate of loss as long as you're not eating less than about 1300-1400 calories and you're getting at least some exercise to help keep you from losing muscle mass.

yeah that is totally normal the first month you will loose more then you will through out your diet! so definitely enjoy it! My first week calorie counting I lost 7 lbs it was glorious..LOL now I average between 1.5 lbs to- 3 lbs! on rare occasions I don't loose at all... or just a few ounces..

I would only up my calories if the 4 pounds a week is consistent for a month or so.

i think personally that 1500-1800 isn't enough. 1800 would be good if you are totally inactive. if your waitressing which can be very hard work you rack up alot of steps per day plus the carrying of plates. etc. and if you work out a few days a week your probaby not enough. you want to keep your calories in vs calories out to a deficite of no more than 1000 a day. i.e eat 2000 burn 3000. this will give you a loss of 2lbs a week. if you let this difference get over 1000 for a prolonged period of time your body starts to drop muscle mass not fat as muscle burns calories.

there are plenty of books/sites and health professionals you can ask if you need help working it all out. your looking for you bmr or base metabolic rate. thats how much you burn per day just sat around. then you need to figure how much you burn at the gym and walking around. a cheap pedometer may help you or following the things on the screen at the gym will be good too.

without being rude 1500 a day for an active person over 200lbs is practically starvation