Gekai Kiara wa Shibou Furagu wo Yurusanai - Vol. 1 Ch. 2

[MangaDex]

 

[Kaarme]

In that world, she's actually the false doctor, as she hasn't got any credentials.

 

[ARealCoolGuy]

Do they even have doctors in that world? Shouting "I'm a doctor!" might do as much as screaming "I'm a whoosemwassit!".
It likely means nothing to them.

 

[Psychronia]

How is she even gonna explain her medical knowledge?

 

[Simpleton]

Do they even have doctors in that world? Shouting "I'm a doctor!" might do as much as screaming "I'm a whoosemwassit!".
It likely means nothing to them.

And here I only came in to mention I felt like she should have gone "I am a doctor!" (Instead of I'm a doctor!) but everyone else has much more valid complaints.