This must be thin from quite some time, as it has life of 1-2 years easy (depending on your braking style). You must have notice coincidentally after the full wash as we dont slam brakes at high speed everyday. This thin brake disc is serious concern and you need to change it asap, however before you get it changed get second opinion as well. As in some case i noted that auto pro guys are big drama and suggest things which may be needed after 6 months as a super precaution to not to have a bad name for auto pro.
These disc should cost under 500 dhs, better check with spare part shops listed in this forum under business listing section.