I have a Sony Vaio VPCF213Fx which had a 4GB DDR3 RAM (2x2GB). The RAM I bought from Crucial was a 1x8GB PC3-10600 1333 SODIMM. Now, my laptop has the screen broken after an unfortunate fall so I always had it connected to an external display. After upgrading the RAM the laptop turned on (screen lights up but since its broken I can't see anything) but it would not show anything on the external display I used (nor on the TV). I tried HDMI connection and VGA. I decided to re-install the old ones and now the laptop's screen is all black and it seems the fan is working at high rpm's. In addition, the laptop seems to have a loose piece inside though I am not sure if it was there before or after I installed since my laptop was always connected to the external monitor.
I am sorry for the issues that you have experienced with your system. I pulled up your system and it appears that the system is upgradable to 8GB but with 2-4GB modules, not a single 8GB module. The recommended upgrades for your system can be found here. As far as installing the old memory back into the system it should just start right back up. Have you double checked to make sure that they are clicked back into place completely? Could the moving around piece be something from the fall?