Well islandgirl25, you could not obtain an actual "temporary resident permit" because that is a different document all together that is only given to those normally inadmissible to Canada. You would not need a visa to enter Canada. It is recommended that you have your spouse with you when you go to the border and speak on your behalf. They will need to do most of the talking unless of course they ask you a question. They will then state that they will be providing for you during your stay and would like that you remain in Canada for the duration of the PR application process. Bring at least a receipt for proof of already paying for the application process to show that you will be applying soon. In which case they will hopefully give you a "Visitor Record" that will be a document that states how long you can stay and when you must apply to extend your stay. They may also give you a stamp in your passport. Either way you will need documented proof of when you crossed the border to extend your stay. Usually you need to apply to extend it 30 days before your status in due to expire. During the wait time, you will "implied status" which means you are still allowed to stay on visitor terms while you wait for a decision to be made.
You can also do what many of us have done and with the original submission of your PR application, you can submit an application for an Open Work Permit with the PR application and have it received before your status expires. This will keep you in valid status for the duration of the processing and then if approved for Approval In Principle (9-10 months after it was received) then you will be given a work permit along with the sponsor/applicant approval for PR. This will allow you in most provinces to get healthcare coverage and you can get a SIN and will be able to work during the duration until you actually land as a PR of Canada. But note, you can only apply for the OWP with an inland application and you want to do it the way mentioned above. And of course if you so chose, you may also after sending off your PR application, submit an extension of your stay separately from the PR application and mention that you are waiting on the decision of your inland application. It should be approved because they know that with an inland application, you aren't not recommended to leave Canada. No matter what, do not subject yourself to being illegal or the worries that follow it. Always keep yourself in valid status.
As far as the medical goes, the steps for Outland and Inland are different as far as forms go but the medical procedure is the same and its results do get sent to the same location from the doctors to Ottawa no matter whether you get Inland or Outland done. But I would recommend you talk to the DMP you went to, to the CIC agents, and to members like Leon, rjessome, PMM, and RobsLuv for how to go about switching your Outland medical to an Inland medical properly. Also, you should also remember that medicals are only valid for 12 months from the time you get it done.