By the time you return for senior year, your original applications should have been submitted. If you are still receiving supplemental applications from individual schools, return them as soon as possible.
Hopefully you will receive interview invitations during this time. The interview process, particularly for medical school, can go on throughout the spring. In fact, many schools do not fill all their seats until late summer, just before classes begin. If you are not accepted, you will have to decide what alternatives to pursue, such as waiting a year and reapplying, or looking at other career possibilities.
With luck, though, you will have been accepted and made your matriculation decision by spring. Then you can graduate from Susquehanna knowing that you will be attending professional school the next fall!