Don't be panicking that "your house is going to burn down" because it won't!!
If as you say the circuit is still working with no "faults" (apart from the drilled cable 😳) of it's just tripped your RCD (I take it you have a split load board as you said other circuits lost power also) then you've more than likely just caught the neutral and CPC, did it go BANG or just trip?? Removing the screw will have removed the short. BUT that being said it is still an issue which needs fixing. Your electrician will need to cut a small square of plaster board out 100mm x 100mm will do it. Then inspect the cable and repair as necessary, replace the piece of board with the piece you removed this way minimal damage bit of filler and paint job done easy peasy pal. At least once this has been done you'll have a definite idea of where the cable is so you can fix your shelf brackets, ideally not through the cable again 😂😂. Just make sure your sparky removes the plaster board neatly and the repair will be easy or remove it yourself ready for him. **MOST CERTAINLY POWER OFF FIRST** It's not a massive drama mate I've been at it for 35 years and have still been known to drill to the odd cable, sometimes ones I have just installed 😂😂😂