So it is tr.im that says:
Your URL contains a blacklisted domain name, flagged as spam. Please try again.
But it says that with any co.cc domain. Try it. I have been putting in random characters as fake co.cc domain names & they all give the same message.
It would appear that tr.im considers the co.cc domain as being spam. co.cc is a domain for the TLD cc, Cocos Islands. When you register a co.cc "domain" you are really getting a subdomain. It must be that there a many spammy sites that are subdomains of co.cc, which does not surprise me as I am sure there are in all of the free "domain name" services.
If you site was considered as spam by Google it would have been dropped from the SERP. I can find pages from your site by searching for "site:upcalc.co.cc".
So why have you dropped from the first page?
Could be lots of factors. If your site is new there is what Matt Cutts (Google guru) calls "minty freshness". This is were new sites rank extremely well when they are first spidered by Googlebot. Over time as they are visited by Googlebot the Google algorithm makes a better decision as to where your pages truly belong.
If you want to rank well one of the factors seems to be links from "authority" sites. When I search for links in Google I only find 1, a Stumbleupon. When I search in Yahoo I find 62, & while I have not clicked on each one many appear to be comments to blog posts. Most (nearly all) blogs are set up where the links in comments arer nofollowed, which means they will be ignored by Google.
Get some links from good sites to do with the subject of your site. And do not link exchange as that is against Google's guidelines.