No change in size it seems

I can't really notice a big change in my clothing fitting even though I've lost 10 pounds, so I get excited when I get on the treadmill and see it go down but what's the point if my clothes dont' fit better? I know it can't just be water weight loss, or can it? I'm still on plan. I had two birthday parties yesterday -- one for a 5 yr old and one for a 50 yr old. I had 1 regular size piece of pizza at the child party and one very small slice and a cupcake. At the evening party, I had a litt