If debugging is enabled there are some techniques to remove pattern lock.The other option is to data/factory reset using CWM Recovery.
The installed apps and contacts will be lost.But there is no CWM recovery installed in your phone then what to do ?. You require usb debugging enabled in your phone to install CWM recovery.
There is a trick to Reset Pattern locked Xperia Phone.
1) Click Emergency Call
2) Enter Service menu code
3) Click Custamization Settings
4) Click Reset Customization
5) Click Reset Customization and reboot button.
Warnning : All your Personal data and Installed apps will be lost, This is only for Xperia Devices,Don't miss use this trick