No, it certainly isn't - for example, one tutor has pupils aged 89, and no doubt there are older ones somewhere.

It's true that professional musicians tend to start very young, as young as 4 in some cases, but this doesn't mean that they wouldn't master the instrument if they started later. Basically if you are so passionate about something that it's going to become your life's work, it's likely that you will start it as soon as you physically can - that doesn't mean that early childhood is the only time to start.

If you start lessons - and I really hope you do - what is more likely to cause you difficulty is not being older in itself, but the fact that, in your early teens, it's that little bit easier to give up when things get difficult. Unlike, say, the guitar, the violin doesn't give a lot of result when you first play it and you usually need a couple of months before you start to get to grips with it. So you have to tell yourself in advance that you won't give up in those first months, no matter what.

In that case there's no reason why you shouldn't learn to play - hope it goes really well.