Like an ugly Piggy JDM rear
Hmmm.... Are all the dark droplets oily, have you scooped some up with your finger, rubbed between fingers or even smelt/licked them? Seriously
Oil light coming on is the worrying sign as that's oil pressure not oil level. Never EVER had my oil light come on and I've had some hard driving sessions in mine (private road/track of course).
Mark on the floor is a hole, I've given the bumper a wipe but I couldn't smell anything. Going to get an oil change done this weekend and give the car a wipe down and go from there.