After flashing, XP does not turn on. What to do please? topic

I have a Xperia P (LT22i) with firmware 6.2.A.1.100. I tried to upgrade the XP with custom Lollipop ROM. But I failed. As a result of my failure, my XP doesn't turn on. I am not sure what went wrong. Hopefully you guys can help me out. For your convenience, I am describing the process step by step that I followed to install the custom Lollipop ROM.

1. I followed Doomlord's Easy Rooting Toolkit for rooting my XP, and I successfully did that. I checked it with JRummy Root Check.


2. I am a Ubuntu 14.10 user. So I followed this guide to install Flashtool. The flashtool was successfully installed.


3. Then I followed this guide to unlock my boot loader. It was done successfully too.


4. Then I downloaded the ROM from here for installing.


5. I followed this video to flash the kernel.

After flashing the kernel I can't turn on my phone. Can anybody tell me what to do to turn on the phone? For you kind information, I am still a noob in this scenario. Keeping this in mind please help me.