just realizing this...

i work in a hospital and help take care of ppl 24/7. so many stories, but today i was thinking about me n my bf... we ve been doing this for a while now, kinda like caregiver play. he likes when i pretend to be his nurse or doctor, checking vitals, writing fake prescriptions just for him... and sometimes im the authority figure, which feels weird n exciting at the same time. it started cuz he was going thru something hard n needed support, but its turned into this thing where he needs me to take charge, even in our sex life. i never thought about a kink like this before. is that normal? how do i explain this 2 my friends if they knew?