What is my mistake here?

1: DOnt start in the back.
1.5: Scout with darts.
2: As soon as you saw air it was time to make AA. It took you like 30s to do this.
3: Around 2:30 it was time to retake those mexes you lost, but instead builders were sitting idle.
4: There is no reason to build levelers that early, ever. You saw he went air..why make levelers at all?
5: Around 4m you sent scorchers off alone without AA support
6: Your com shoulve morphed something like particle beam and walked on over to mex spots - banshees cant kill it.
7: At 7m you finaly got footholds on other mex spots, but your opponent got them on all but 1 - you are very out-expanded at this point - its pretty much game over and nothing after this point matters.

I dont see any issue with starting in the back.