I trained as a teacher in my early 30s and I was exhausted even then - I can't even imagine how wiped out it would leave me in my early 50s (I work for the NHS in a library/education related role). There are lots of other things you could do if you enjoy working with kids - information officer type roles; or if you enjoy education - education or training officer in the NHS or other large organisation, just as an example. At least you'll mostly be with people who actually want to learn, or at least are too polite to give you a hard time about it....Couldn't you look at something like teaching design part-time if you're dead set? The new T-Levels will be coming online soon, although as others have said, FE isn't exactly the most secure career choice, it's pretty much all sessional these days, with a few exceptions.
(Oh, and my teacher friends the same age as me who are still in teaching would also say "don't do it". One of them has just got their HGV licence, though continues to teach and tutor a bit part-time.) On the subject of vacancies and the government continually trotting out the "there is a shortage of teachers", my somewhat cynical but extremely accurate interpretation is "there is a shortage of young, cheap teachers in places like central London" and/or "there is a shortage of devoted experienced Academy Leaders who we can rely to bleat the party line about how utterly fantastic the government reforms are". Although perhaps 30-odd years of sitting in pointless management meetings (even in a non-teaching environment) that repeat around every 11 years or so has left me somewhat jaded...
Certainly where I'm originally from, the North East, there really isn't a teacher shortage, and permanent, full-time jobs are like gold dust. (Though that isn't only teaching, to be fair...)
And on a slightly different note, like you, I loved English at school (didn't do a degree in it for a range of reasons); but I'm not sure the way that teachers have to deliver it now bears any resemblance to even the very grammar-school-type method my secondary school used - I don't think I'd enjoy it much, these days.
Good luck though, whatever you decide to do.