[Have submitted a sitemap and got admitted several days ago however when I check if google index my pages, I found google indexed pages under tags instead of URL in the sitemap. you know URL in sitemap is what I want google index. URL in sitemap is like mydomain.com/archieves/page1.php
URL under tag is like mydomain.com/archieves/tag/tag name
what is more, I am still sort of confused. if Google will index pages in a sitemap, it will find duplicated content between URL under tag and URL in the sitemap. will this cause penalty?]
Google doesn’t crawl and index all of your websites in one go. They will come back to index more in a few days. Be patient, they will get around to indexing them all.
I sound as if you are using WordPress if so there is a free plugin called All-In-One SEO that will help you solve the tag page indexing issue.