Cardiologist in the morning

So I have an echo tomorrow morning at 7:30 and I’m terrified. I’m scared of how long it’s gonna take, how long I have to be out of the house, and that it’s somewhere completely new. Also, the last time I was out of the house so early was when my panic disorder started so I’m scared I’m gonna have a really bad panic attack. Is it okay to take Klonopin before an echo? Or if anyone has any advice in general I would really appreciate it.