On a chestnut burr I would always use the colour to enhance the grain. It would seem to me you just sprayed it on top. The trick here really is to start with the darkest colour, give the whole piece (or a large section) a complete coat, and then sand it back so that only the soft bits retain some colour, then repeat with a lighter colour. In that way you will get a much more impressive result.
Search google images for "Phil Irons Urns" and you will get some nice examples of what can be done. You are not far away from that.