Felt tip? Hm.. :)
I think you should have magnified, as in, zoomed to the center of your picture than rather focusing on the whole picture. The whole picture seems pretty good, except for the triangles, where do they come in tapeworms?
I think you'd get better comments if you zoom into the center- To what I can see from it, it has the perfect details that give it the look of a felt tip pen. Keep up the good work. Michael.