Leave the Taquitos. Take the gun. Use it to kill and gain experience at the modern magic of killing people. If you could gain experience by aiming your science at rocks, then life would be boring -- no challenge. "Today I scienced 100 rocks and gained a level." It doesn't work that way. I bet you don't even know what leveling up feels like. You have to aim it at people. A full professor is 35 XP and up, and just like with the Assassin's Guild or high-level monks, there's limited space at the highest levels -- you have to take somebody down before you can progress.