Guess you'll have to reexamine everything you're doing, like how you're mixing your hcg, are you refrigerating it after the mix, are you eating only the foods allowed, are you eating at least 500 calories, are you combining veggies (you shouldn't, unless it's a salad as specified in KT's book), are you eating different foods for both meals on the same day, are you drinking enough water, etc. Once you've eliminated the possibilities as noted in KT's book, then it's probably temporary. You may either wait another day to see what happens, or do an apple day.
A 3-4 day plateau is common. I've hit a 3-day one myself after 10 days, but noticed I made an error in calculating my last meal. I went 130 calories over!
