From my understanding (please take my 2 cents for what they might be worth) if you have hit "starvation" mode, you have lost some lean body mass (muscle) as that is what your body will burn if it has nothing left to burn. The best thing you can do to "boost" your metabolism is to do some strengthening exercises. By that I don't mean crazy weight lifting. You can use use tension bands (those giant rubber band things) if you have them. Or you can even use bottles of water (get at least the 1l size). And although, I can't think of anything off hand....I know there are some articles on the web about homemade weights for light strength training too. Obviously up your calories properly. As far as how long til your body "trusts" you....well I imagine everyone is different, but the good news is, if you've only slipped up on the calories for a short amount of time, you haven't lost that much muscle mass. Just make sure that you keep up with your diet from here on out....I think you'll be fine!

Good luck!!