GunacaZ28

Last night I was woken up by my brother telling me my car was in the street. I have a sloped driveway and my e-brake doesnt work so I usually just leave it in gear. For some reason last night the car decided to go for a roll. It didnt pop out of gear or anything. When I started the car it was making a tick noise. It almost sounds like a rod knocking.. Its pretty freakin loud! I drove the car up the drive way again and left it in gear and shut it off let my foot off the brake and it started going right back down. The main thing Im worried about is the noise though. It ran great the night before, but the clutch has been starting to feel weak. please help if you think you might know what this noise could be! The car is a 98 z28 bone stock, with 108,000 on the clock. Thanks!