Hi Panzhuli,
Can you clarify what you mean by “nothing there?” It sounds like you are seeing a Control Panel (ie, you can see the design, the color scheme, etc…) but that the only Tab available is the “My Account” tab. Is that correct? Or are you seeing a blank screen or un-styled text?
If indeed you are only seeing a My Account tab or something similar, than there is a good chance your account on the installation is not a Super-Admin account and that you don’t have the privileges to see other parts of the control panel. If that’s the case, you’ll need to have whoever has Super-admin control of the site increase the permissions your account has.