First, your body may be adjusting so don't panic.
I gained a few lbs in the start too and then quickly went on to lose 11 lbs the first month. Watch for hidden carbs also....and keep strict tabs on everything you eat....use a carb counter to help. If you must, measure your portions (my handy measuring cup and my postage scale helped in the beginning)..I was shocked what I thought was a 1/2 cup serving was really a cup and thus I did not accurately keep count. I learned.

Good luck!