It's for a place called Wag Time, it's like a doggy day care/grooming. I really hope it's not his decision else I'm royally screwed.

Hey don’t sweat it.
The interview I had for the job I’m currently at, the lady was such a stuck up bitch that shot down all my attempts at small talk, any laughing in the conversation I did alone while she death glared me, etc.
I got hired anyways, and although on my first day I told them I wanted to be in a different branch, the same lady has begged me at least once a week to come back to her department.
Don’t let that discourage you!
Some people like to test how well you do with differently rounded individuals.
And if you somehow don’t get the job, it’s just a door closing for another to open.
All it means is there’s something so much better for you in store!
You got this!

"Some people like to test how you do with differently rounded individuals" This - especially in tag team interviews. Don't lose hope (and, hey, if the second was a nit-picker, go look up what the actual answers are, now that you can? If they call you back for a second interview, you'll know you have it down, and, more to the point, you'll show them you can learn, quickly. A driven newbie is often better than someone who "knows everything" but is just putting in time, from a business perspective).

Also, send then a quick phone call/email, saying "thank you for giving me the interview, I look forward to working with [your company]" - it shows you are trying, without making them read more than they have to. maybe it won't make a difference, but most HR people (or bosses wearing HR hats) don't get thanked much in that role, so it might improve your odds.

:3 best wishes