I did my first test a few months after my 17th bday (my brother ended up teaching me to drive so I learnt quickly) and failed first time because the examiner made me feel bad throughout the drive. I was nervous because even though I was confident with driving, he did comment on my age when he saw my provisional. Nothing bad, and looking back he wasn't criticising my age, he was just a bit weird. But he criticised me for everything, I mumble sometimes when I drive, e.g. if I'm on a roundabout I'll whisper something like 'can go now because they're going left' and he'd say it was distracting and inappropriate to mumble. I went 29 on a 30 and he looked at me and said SLOW DOWN: going over the speed limit is a major. I complained, nothing happened cause it's all hearsay (though my instructor that I had a few mock tests for) said he was inappropriate). Ended up failing because I went too forward in my bay parking and went over the front line (if that makes sense).
THE NEXT TEST, I hear my name being called and it's HIM. I panicked hard but he didn't even remember me. I passed, he was the same and critical but I literally ignored it. The only time I opened my mouth was for the tell me question.
Don't be put off, it's not a big deal imo to get the same. But it's easy for me to say that now that I've passed. HOWEVER, try to avoid booking it the same day and time. Both my tests were the 8 o clock slot on a Tuesday.