It could be any number of things. Make sure you're drinking plenty of water and watch the salt. I put on 2 lbs in the past couple of days, which I knew I would, since I had a meal with soy sauce in it the other day. So I upped my water, and have lost most of it. Could it be TOM? I gain a few pounds that time of the month, too. Just don't weight yourself everyday, keep to about once a week. It'll come off. You've lost 10 lbs so far, which is great, since you've only been at it a few weeks.