its only been five days? i would give it atleast say around ten days.. if you don't see anything by that point, i would write it off and start over..
heres a few tips as well.. keep the rockwool moist.. not super wet, and not too dry.. you can also place the rockwool into a plastic baggy that is closed all for about an inch or so to help keep the rh up..
keep the temps around 80 f.. this is about the temps that seeds like to germinate in..
goodluck m8...