a 3 lb gain is nothing compared to the amount you've lost. those 3 lbs will come off quickly, and they are not a reason to allow yourself to give up after coming so far. if anything, this should serve to further motivate you -- 3 lbs feels bad, but what about another 30? don't allow yourself to make excuses; you will seriously regret it. just go back to the same pattern you'd had before, and as time passes, tweak it a little -- that you fell off may mean that you're not doing what your body needs, so finding a new plan might help.
oh, and just so you know, i did fall off the wagon pretty hard after my fist weight loss journey, and i ended up gaining almost all of my weight back. i was only 7 lbs away from being completely back to my starting weight when i finally snapped out of it and i've been kicking myself ever since.
