Can i wait until my next doctors appointment to tell him i got vaccinated? or do i have to call and tell him right away?

It is reasonable to wait. Vaccinated for what? COVID, flu? I hope both. But if you get sick with something be certain to tell them.

Many times your primary care doc is informed by the entity giving vaccinations if provided them with the name and/or office address. No need to rush otherwise, take your immunization card/confirmation with you at next visit.