I have quite a few friends through my voluntary work that are studying Paramedic Science or are qualified. I think it is one of those careers that appeals to and is open to both school leavers and later career changers. Check with the Uni or go to an open day, I imagine you will find that a large proportion of students are post college and I doubt this is discouraged. There are other routes too, for example ambulance technicians can still progress to paramedic with on the job study while with an Ambulance Trust.
I see that it is a physically and mentally demanding course and then career. Although it is a glamorous and respected role it doesn’t have the same financial rewards as medicine despite a high level of responsibility, risk and probably stress. It is however an interesting and very important role. See if you can get to speak to some student and qualified paramedics at various stages of their career.