Why is my keyboard on my iPhone messed up?

I dropped my phone while I was riding a hoverboard as my friend had ran into me. i'd say it was a pretty hard hit on cement and it flew a couple feet away.After I picked it up there were lines on the screen, but it disappeared after I restarted it. Now my keyboard is going all crazy with some keys unresponsive and if I hit some keys the letters just triple even though I only hit it once. Please help thank you very much.