I have a big and strange problem with my DS

Let me explain.My ds won't turn on and when i try to charge it orange light flashes for few seconds but if i try to power it on when it is attached to the charger the green light flashes and then goes red and if there is a game in the game slot my DS'green light flashes and then turn off but sometimes the green light stays and it will power on but when I try to load a game it crashes.Can someone help me?Please