HP dosent care about its customer's

HP Pavilion dv5t Entertainment Notebook- Ive had my laptop for 2 months and now the screen is distorted. I closed the laptop and when I opened it 5 min later I had lines running down the screen and half the screen was not readable. I sent it back to HP and they said that I might of put pressure on the laptop causing a crack. But I know there was no crack and I asked the rep so look at it. He then backed off and said it was internal. They want 400$ to fix it and I paid $800 for it origianlly. After 30 min of me arguing he said they would do it for $200. I cant believe HP is doing this. I did nothing to the laptop and now they want me to pay to fix it. Help me please