Well, as I assume you just went out and got the nib new from the store, my first question is whether or not you removed the new shiny coating? As this site
says, the manufacturers put a rust resistant coating on the nibs to prolong shelf life. The site also lists several other troubleshooting tips that you can utilize.
As for calligraphy itself, until you get used to your new dip-pen, I would suggest inking copies or prints of your work that you want inked. That way you won't "ruin a good picture".