Dropping the tablet may have damaged the internals of the camera, or cracked the lens. The camera however is easy to replace in the Lenovo IdeaTab S2109A-F by following the replacement guide under camera hardware problems on the Lenovo IdeaTab S2109A-F troubleshooting page. Replacing the Camera takes minimal effort and should resolve the issue your having with blurry and soft images, as they are symptoms of a broken camera.

Your Lenovo IdeaTab S2109A-F may have a faulty battery. Since you plugged it in to the charger and it stayed on that eliminates the possibility of a broken power adapter. You can replace the battery in your IdeaTab with minimal effort by following the Battery replacement guide found under Faulty battery on the Lenovo IdeaTab S2109A-F troubleshooting page.