There are quite a few people who decide on med school after they’ve completed college or nearly completed it. You won’t be able to start next year, but most don’t start right after college either so you won’t be unusual.
@WayOutWestMom knows a lot about the whole med school process and your options - far more than I know with specifics.
Otherwise, make an appointment with your Pre-Health department at your school and someone there ought to be quite helpful too. If there’s room in your schedule, you can start some Pre-Reqs next semester.
Meanwhile, see if you can shadow some doctors. It will give you an idea if med school really is the right path for you, plus, it’s 100% needed for successful med school applications. A Pre-Health advisor at your school should be able to point you in a direction to set this up. You will likely have to make contact, but they should know where you’re most likely to be successful asking.