I'm sorry to say this, but your 3DS is probably corrupted.
Try:
# Replacing the ***battery***
# Maybe you do have CFW. Try holding the ***select button*** while booting up. If there is a menu, you have CFW.
# Try removing the ***SD Card*** or ***Game Card***
# Try removing the home menu extdata. (You can do this with a guide on the internet)
If you do somehow have CFW or these don't work, ask me for more help.