Years ago, as a student pilot, I remember the fear when my instructor told me we would be flying into Class B (then known as a TCA). What happens if I miss a call? What happens if I blow an altitude, or screw up a heading? He kept re-assuring me that I would do just fine. But I wasn't convinced.
I made contact and entered the airspace, flying my assigned altitude and heading with sweaty palms, listening to the pros.
Suddenly, ATC, in a very cynical, condescending tone, barked out "Northwest 560, WHERE are you going?"
A rather timid voice came back with "Heading 260, sir."
"I said 360! Fly heading 360. Just where do you think the airport is?"
"Roger ... 360" was the reply.
"Cessna XYZ, fly heading 300."
"Heading 300, Cessna XYZ."
"Thanks, at least SOMEONE here can follow instructions."
From that point on, flying in controlled airspace was no sweat.