Im totally confused about changing PR?

I’m not familiar with how Link Metro works, but I do know that the Toolbar PR is not the real PR for your site. Google updates the real PR behind the scenes, but only updates the visual PR (what you see in the Google Toolbar) every 3 months. I’ve seen a couple of sites that try to estimate what your real PR should be, but I’m not sure how accurate they are. Here’s one you can look at:
http://www.seologs.com/pagerank/prv2/pagerankv2.html