Let me get this straight. You use paint to draw an image and you use photoshop to resize it? Why not just use the far superior photoshop to draw the image in the first place?
I find that Photoshop is too complex for quick drawings like these. Like in photoshop, the fill tool has it's own settings, and if set wrong it covers some stuff or covers the whole pic. With Paint, it's simple, just make a closed space, and click the fill tool and it's totally filled, no muss no fuss...