Although true that experience would be a really good idea, course length into teaching does not have to be so drastic anymore. If you decide to do teaching, then I would recommend doing and Access to higher education course at your local college and then doing a 3yr undergraduate BEd course that allows you to qualify as a teacher without the need for Post Grad, so all in all it would take four years.
It is true that some universities do look down their noses at anything but a levels but more and more fairly reputable universities are realising that a levels are not for everyone. Its is perfectly possible to do an access to higher edu course and then do a 3yr BEd at a half decent uni.
Good luck