My xperia c won't start topic

Hi every body
I tried to install Lollipop Rom from this topic:
at step 4, I've downloaded Mobileuncle Tools app and updated Recovery then the phone turn off and doesn't start anymore.
- I holed down the power button for more than 30 sec > nothing happened.
- but when I holed down the power + volume-down keys > the color lights flash but nothing display on screen.

please someone guide me how to fix this problem and I will be appreciated.

thanks :)
and am sorry for my bad language.