
Haha... I am guessing then probably level 8 after that ????
Yes, it goes normally until level 10. After that, it's a bit more complicated, as they used a different equation. So you go from level 10 to 13, then to 17, after that down to 12, if I remember well next is 15, and so on until you've gone through all levels between 10 and 20. Then it goes normal again.
That's pretty much a point where you go "but what were the developpers thin(smo)king ?"