Hello,
From what I understand, the 2 wires fell off the Molex connector for the pump of your H100. You put both of them back in the plastic shell, but inadvertently inverted them : For example, you replugged the one that was on the left to the right and vice-versa.
From that, I gather that many different things could have happened :
1. You short-circuited your PSU, which in turn short-circuited your entire PC, which could now be completely dead.
2. Only the PSU was short-circuited. You would need to find a new one.
3. Only the H100 was affected. Having inverted the wires made it so that the pump and the fans connected to it started backward, which damaged it completely.
The first thing I'd do is put another PSU in your PC and see what it does. If it starts normally, go in the BIOS and check your temps. If everything is ok, then it was simply the PSU that was damaged.
If replacing the PSU does nothing, then there's a greater risk that the entire motherboard was short-circuited.
Good luck,
al360ex