Almost done with level 12

I started playing this game not too long ago and felt like leveling up was really slow. Later, I realized it's better not to hire haulers! Because you only get experience points when you haul things yourself, I'm level 11 now. I wonder if another hidden quest for level 15 will pop up after I complete level 12 🤔 But I think I'll just play until level 12 because there are quite a lot of ads.