Depending on the thermal interface material applied from the factory on the HSF, it can be very difficult to install the spring attachment on the HSF. You may or may not of actually damaged the CPU. I'd suggest removing the mobo and setting it next to the PC case on a non-conductive surface such as the mobo box. Newegg has a video on this I believe on their website. What you are doing is eliminating any chance of a short circuit from the mobo touching the metal case. You can start with the very minimum of 1 DIMM in whichever slot your mobo owner's manual requires. Install the graphics card and HDD if desired and try booting the system being sure that all power and communication cables are attached.
Without the HDD you'll get an error message saying no storage device is installed. If the system boots as a bread boarded set-up out of the PC case, then you need to find where the mobo is touching the metal case and shorting out and fix the problem with spacers or electrical tape or whatever is necessary. If the system still doesn't boot then I'd remove the HSF and inspect the CPU. If you see no damage, I'd remove the CPU from the socket and inspect the pins for damage. Always align the triangle on the CPU so it aligns with the matching triangle on the corner of the CPU socket. Gently but firmly press the CPU all the way down into the socket.
Hopefully you'll find some simple, easy to correct issue and be up and running soon.