iphone4 not charging, pls. help!

Keep on Wall Charger and Reset, hold both Home and Power buttons until the iPhone restarts itself, ignore the "slide to power off" slider, let it restart itself.

I'm also having a problem with charging. I tried to download photos to my computer (which didn't work) and now it wont charge on any charger. My husbands phone connects to same computer and will charge on all chargers. I have tried the reset described above but it said to connect to a charger (it was plugged in).

Please help!!! I have less than 20% charge left. Had the exact same problem a couple of months ago with my original phone which was under warrantee. This one is not!