New owner, master warning light

Hello all! I'm a new owner of a 2006 Prius. It had no problems when I bought it 7 months ago until one night after work. As soon as I pulled into my driveway, the car kind of felt as if it (jumped or jerked), made a loud, growling/grinding noise followed by Master Warning icon and immediate smell of oil. I constantly keep a check on my fluid levels because I drive a lot of miles. Now it seems as if something keeps draining my small regular car battery and the car won't go over about 3mph. I've taken it to a dealership and they know as much as I do. Can anyone help?