Should it hurt this much?

Ok so I went quite a bit further yesterday - 6 1/2 miles or so (get me) - and it felt ok mostly except towards the end by left hamstring (I think) started feeling a little painful. This morning my left ankle is aching and I keep getting shooting pains down my left thigh (hamstring or sciatica???)

I was pleased with myself for getting so far though. Of course it means that's now the normal route and I have to go at least as far every time I venture out. I might have to fight the urge to do that - it seems running for over an hour doesn't do me a lot of good. How on earth did I ever finish the 1/2 marathon?? (training? Determination??)

It will get better though, I'm fairly certain of that much at least. As long as I keep going. Should I invest in new shoes? These are 3 and a bit years old, but I haven't exactly run a long way in them. Perhaps the thing to do is to try out some different ones in the shop and see if I can tell the difference. Gait analysis would be a good option as well.