Tilly,
I've read it takes 2 days for your body to process out the carbs that you eat. So if your eating low carbs for 2 days then you should be in ketosis tomorrow.
I've had times when I've gained weight, how discouraging. It seems my weight fluctuates up and down, but it has been going down more than up.
Like I said before, it is so important to stay on the plan, no cheating. It's a commitment and it is hard at first. It will be so much easier when you've done it for 2 weeks. I can't tell you how much better I feel. I use to have no energy and felt so tired. Everyday I just couldn't wait to take a nap or go to sleep. It was the sugar! I feel alive now. I'm just a different person.
For at least the first 2 weeks, stay away from alcohol. I like it too, but it's important. I didn't drink for a month. Then when I did, I found out it took a lot less to get me tipsy. I use to drink all night, so that was something new. In fact, I don't really like feeling like that anymore, so my drinking has really slowed down. And that's good. Alcohol is one of the biggest reasons we gain. Even if it is low carb. Besides, it lowers your inhabitions and your more apt to eat stuff you shouldn't and you eat more because you can't tell that your full. I'm sure you've heard of the new low carb beer-Micolob (sp?) ultra and Miller lite is lower carb too, if you want to indulge.
Realize that you are not cheating yourself out of anything when you are eating this way. You are doing your body a big favor. Your creating a great environment for healing, cell building and weight loss. The foods that you find tempting now, will not look so good in the future. I ate a candy bar a few weeks ago and I was sick for a day and a half. I didn't really want it to start with, and when I got so sick, I knew that was the last time I'd eat that.
If you need any website addresses, I go to lots of places for information and support. Let me know if you do. Nikki