Ah yes. Well, nothing to worry about, it is perfectly normal. You've zoomed to the point where normal graphics get turned into iconographic representations of themselves. Use your mouse wheel to zoom in/out, and if that fails, use the + and the - keys located on the main part of the keyboar d(not the numeric keypad, but the other part).

Your game functions fine... but once you try large galaxies and above, you'll enjoy the zoom function, just as we all do. It gives you a bigger view of things.

You definitely are using the "tactical icons" instead of graphics. I know because my computer is so slow that I almost always play the game at that level. Go into your "main menu options" and look for an option called "tactical view zoom level." It's probably jammed all the way to the right (or left, I forget which direction does what) meaning that the game shows icons even when totally zoomed in. Try moving it to the center of the slider and going back to the game. Zoom in - at a certain point you should get your ship and planet graphics back.

It's entirely a matter of your preference, really.