"doctor" versus "doctor's"

Hello! How is it going?

1.-I went to the doctor.
2.-I went to the doctor?s.

Are both correct?
I?ve always said “I went to the doctor”,
but yesterday I saw someone
had written “I went to the doctor?s”.
What?s the difference?

Thanks a lot!

No difference in meaning; it a regional or personal use. Doctor’s is presumably a short form of ‘doctor’s office/clinic’.