I woke my phone and it was working fine till I went into apps and they weren't loading. So I shut down my phone. Well when I did that it never turned back on and now it's a black screen with a loading thing on it. I don't know what to do so can someone please help me?
First try resetting the phone by holding both home and power for ~10 seconds, see if it manages to boot.
If not, plug it into a computer and see if iTunes will recognize it and offer to restore it. If it doesn't then you'll have to put the phone in recovery or DFU mode and force a restore.
This also involves pressing home and power simultaneously, but to keep pressing after the first reboot when the Apple logo comes up, while the phone is connected to a computer. Apple provides further information here
If my iphone wont turn on and after I try everything i can, then I replace the battery.