I'm not sure if this is the correct forum but i figured I would post here. So i've been working on a problem set for my first quantum field theory class consisting of 3 problems since 10am this morning with nothing but a few 20 minute breaks to eat, i just finished the second problem after 17 hours and 20 minutes. I'm just wondering if this is something unique to the beginnings of quantum field theory (i.e. before we have started path integral formulation, we are still doing chapters 5 and 6 of P&S) or if this is what I have to look forward to for all my studies of QFT? Thanks in advance for any comments.