My eyes really hurt when I focus on something close up?

I also get headaches and stuff. I'm 42 if that is any use. This year, I've been really busy with work and have been doing a lot of my Christmas shopping and stuff on my iphone. When I'm using my iphone, I have to hold it out at arms length to read what it says otherwise its a big old blur:-S also, I think my eyes are working a lot harder than they should be, because I have to squint to make out fine print otherwise my eyes begin to water. I don't know wether it's just because its Christmas and I'm stressed or I might finally need to invest in a pair of reading glasses:-/

This is a great sign that you need to get glasses. Eyes are muscles that when excerised too often (such as work or using your phone too often) become tired and do not perform as well. Take a break and see how you are. If it persists see an optometrist as it is likely you need corrective lenses. It may even be like you stated that your glasses need to be changed. The reason for this is because your eyes adjust to whatever lense it see through, hence after time your eyes adjust further and may need to be changed. Hope this helps, take care.