If your child becomes unhappy if you remove the things he likes, like polish, dresses, etc. Then he could be expressing gender issues. You are right to let him experiment to remain a happy kid.
There are support groups for trans (if he is) kids, such as http://www.transkidspurplerainbow.org/
http://www.transgenderchild.net/reso...upport-groups/
http://www.transgenderchild.net/reso...upport-groups/