Why is there a black screen after applying thermal compound?

My heatsink was overheating, so I decided to add new thermal paste. I cleaned the old thermal paste off the heatsink and cpu with a lint free cloth and 70% Isopropyl alcohol. When I cleaned the cpu, I did lift it off and touched the bottom, so I wiped the bottom with the lint free cloth. I applied new thermal, placed everything back, and plugged in the computer power and monitor. The fan automatically ran, without actually having the computer on. I pushed the power button, nothing, just a black screen. The power light is orange/amber, not green. I did notice that there was one short beep when I plugged in the power. I already unplugged the power, pressed the power button for 1 min, and plugged in power back in, but the screen is still black. I don't think I misplaced the cpu. Did I apply too much thermal paste? Do I have to remove and apply thermal paste again if I readjust the cpu? At least there is no more hot heat coming from heat sink. Hopefully I did not accidentally damaged something. No damage is visible.