Instant Karma

Can karma really exist? And, if it does, is it possible that it's spread over multiple lifetimes? Cuz, I can't remember any heinous acts that I've committed since the late 70s and I'm being beaten with the Karma Billy Club. I must have been a slave owner or bore Hitler in a previous life. OK, maybe not that bad, but I probably was a klan member or textile mill owner. That's the only logical explanation. If I were 10 years younger, I could bust out a philosophical proof just to show you. But you'll just have to take my word because I'm not as smart as I used to be.