You are definitely not too old. I was 47 when I did my school based training, now 55 and still teaching, generally happily.
Quite a high proportion of new teachers quit before the end of their first (NQT) year and up to half leave in their first five years. So you have plenty of time to have a career that is a lot longer than the average! Head teacher attitudes will vary, but there are plenty out there who will give you a chance if you show promise, very few would be prejudiced against you because of your age, as long as you come across as energetic, competent and willing to learn.
Teaching is not a soft option, the hours in term time are long, particularly for the first few years, and you work a lot in holidays too. You are very vulnerable to changes in government policy which may or may not make sense to you. In the right school, it can still be a rewarding and fulfilling career. In the wrong school, it can be a nightmare.
Because I did a school based route, most of us were career changers, ex TAs or returning SAHMs. The drop out rate was quite high. It's hard to explain just how tough those first few years are, however much relevant experience you have and however good you are with kids. I knew it would be hard, but I think it's a bit like having kids, you can't quite comprehend it until you go through it! You need to have a lot of support and self confidence, know that it is tough for everyone and trust that it does get better as you start to know what you are doing.
I have ended up working in a small special school, very demanding but with a fabulous supportive team. I know I am making a difference to some very vulnerable children and have no regrets at all about my career change. Talk to as many teachers as you can, get some experience volunteering in a school, and if you decide it is for you - yes, you can do it!