I'm on my third whole 30, and on the first one I got REALLY hungry a couple of hours after I ate. I also think that a diet high in veggies "feels" different in your stomach - so sometimes I would be confused about if I was hungry or if my stomach just felt different than I was used to. I would take chicken broth (sometimes with coconut milk in it), a baked sweet potato and hard boiled eggs with me to work in case I needed something between meals (i.e. was distracted enough that I felt it was effecting my ability to work). That all seemed to work itself out in a few weeks, and on subsequent whole 30's I haven't noticed it as much.