Try disconnecting the battery, pressing on power button for ~15 seconds, reconnecting battery, then the screen, then rebooting (pressing power+home buttons together for ~10 seconds).
If an image still does not appear, your need to try a new known good screen, as there is a great chance you damaged the screen during the first repair attempt. It happened with me once although I am a 100% sure I did everything right! And that was like my 100th screen replacement.
If a new screen does not solve it, only then you need to look more carefully at the board. But from what I can see from those blurry pictures, there is no "apparent" damage. A thorough examination with 10x or more magnification is needed (or much better picture).