That's more than doable lipostruggler!! Stick with it and those 21 pounds will be gone before you know it! Water is the key so get drinking, just not too much at once...I drink 3 litres throughout the day. I'm only on day 5 and I feel better already, first day I've woken up without a headache, progress!!
I've done Lipotrim and cambridge before and the weight did stay off after, it only came back because of my bad habits!!