brendan: being no expert, i would assume that it has something to do with your age. Homo sapiens, though generally sexually mature at your age, do not attain their full size until their late teens. they will however continue to grow throughout their life, particularly in the stomach region.
Greebo: There's no shame in being a newbie! Without people like you, our toast community would die out with the more experienced eaters.
As to your question, keeping two pieces of toast on the same plate is fine. There is however a tie in with the margarine question - some eaters (myself included) will leave one piece of toast in the toaster while 'buttering' the first piece. the second piece is then removed and buttered, while still hot. This assures avery even application of melted margarine, and in this way the two pieces of toast will do very well on the same plate.