The plan you had was built by someone with less information than you have now. It stopped fitting. That is not failure, it is an update you have not accepted yet.
Being lost means you left the place you knew. That is the cost of going anywhere new, and you did go somewhere.
You do not need the whole map tonight. You need the next honest step, and you can usually see that one from here.
You are not off track. You just built the track from someone else's blueprint and it stopped fitting.
Nobody is supposed to be doing anything. The word supposed is doing an enormous amount of unearned work in that sentence.
You are not lost. You are between versions, and between is a real place with no signage.
The person you were stopped fitting and the next one has not arrived. That gap is uncomfortable and it is also the whole mechanism of changing.
Meaning is not found. It is built, usually out of unremarkable materials, on days that do not feel meaningful.
The question of why it matters is much heavier at 3am than at 3pm. That is not philosophy. That is biology.