You are likely fine as long as you are getting adequate protein during the day and most P1 menus are fairly protein heavy to begin with. Most of the early rapid weight loss is more water weight than fat loss as you deplete glycogen stores for energy sources that also release water bound to the glycogen during the "storing" process. (It's part of the biochemical process our bodies use to store readily available energy when we get a bit short on carbohydrates from the foods we eat.) It won't continue at that rate so enjoy it for now!

By the time you are at or near goal weight you will still be in the 1-2 lbs per week range ON AVERAGE. Which means a lot of weeks ahead with little to no loss too, so it will all work out in the end. As I like to say, weight loss is neither linear, predictable, nor comparable!

As long as you following the meal models fairly closely, getting in a good balance of lean proteins, good fats and healthy P1 carbohydrates at your main meals and in your snacks, you still should be getting adequate nutrition to support your overall health.