Runrabbit - don't try and do two things at the same time - calorie counting and low carbing won't work. If you are low carbing then you are also 'high-fatting' (or if you aren't you'll probably be starving, as you have been today) and if you then look at calories you consume its likely to be scary because of that 
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If you want to low carb, definitely get over to the Bootcamp thread.
Similarly, if you want to calorie count (though I really wouldn't advise it), there is a board for that too, at least with that no food type is banned.
Personally I would try applying just a few rules to start - don't eat pre-prepared processed food. Cut out sugary foods (only go for those with naturally occurring sweetness, as with fruit, but avoid juice, have only whole fruit), nothing made with white flour, no other white starchy carbs (rice, pasta, potato). Have lentils, sweet potato, beans, chickpeas and if you really want to, small portions of brown rice or pasta, good quality brown bread. Real, whole foods. as much of all this as you need to satisfy your appetite. Plenty of water. Plenty of veg. Forget about calories. Forget about fat. Just try that for a couple of weeks and see how you feel...you may want to take it a step further and low carb properly, or maybe look at paleo (caveman type diet) boards and try that....or you may feel pretty good and that you are steadily losing weight and happy to continue eating that way. Experiment to see what works and what you can live with. There is no point following a diet that makes you feel deprived, inevitably you will revert to the foods you feel you are missing and any weight lost will be back with a vengeance.