If the low speed needle is turned all the way in it can catch the mid needle and turn with the low speed so I would check the mid needle anyway.
set the mid needle first then the low making sure they dont stick toghether (only if the mid needle needs adjusting).

example if the LSN has been turned out 3 turns but the MSN has stuck for 1 turn the LSN has only been turned twice or the other way of course.

Good luck for tomorrows tinkering lat us know how you get on.