That's great, especially the saving money part. And I'm sure many people started out a small business from money saving ideas like this. Why don't you compromise, if you feel uncomfortable about selling the pattern, just charge 99 cents. But I think you should charge a bit for the pattern and instructions and make yourself a little money. You deserve it! A great job!
Thanks inmepyjamies. You comment encouraged me to think about making it to earn a micro income :)