You'll have to clear the cookies from qqTimer. i.e., all of your stored times will be wiped. Click the wrench in the corner, to the right of the URL bar. Then click "settings". Select the "Settings" tab on the left, and scroll all the way down. Select "Show advanced settings..." Under the Privacy tab/section, click "Content settings" and then under Cookies, click "All cookies and site data..." Scroll down until you find qqTimer.net
If you can't find it, then search for qqTimer and it should show up. Click the "qqTimer.net" box thingy, then the little x to the right of the website. That should clear all of your sessions, cookies, preferences, etc.