Not necessarily fucked. It is true what freestylah said about paper. Pick paper that suits what ever you want to use it for. Probably you should not say "enema schematics" to the clerk at the art shop.

If you explain that you want to do some technical drawings and add colors to them the clerk at the art should be able to help you better realize your perverse and antisocial fetishist diagrams.

Have fun Alex.