Hi Kate,
I've had six without sedation..
Try and go in in a relaxed state...they played some music for me during my blocks..that was helpful!! Maybe you can bring some of your own soothing music that you like if they will allow that!!
My lumbar blocks took about 20 minutes to half an hour..before you know it, it's done!
Let us know how it goes!!

Take good care!
I'll be thinkin' 'bout ya!!
Hope4thebest (((((( hugs))))))