There is only 5 Acts to go through. I think your somewhere in Act 3 maybe, but I don't play as much as some people on here, lol, I'm sure some people can tell you exactly where you are. And act 5 goes by pretty quick, just to let you know. I beat the entire thing (solo) in about 10 hours or less, and I'm slow compared to most people.
EDIT: Before one of you take a pot shot at me, I'm slower than most at games, not in general.