No it's not the sardines, it's just that my body is used to eating full meals. And a small can of sardines is just not enough to give me the nutrients and energy that I usually ingest at that time of the day. So in short, by starving myself I'm also starving my brain.
IANADr. But it is my understanding that the fish would have been the ONLY thing feeding your brain while your body was shutting down to conserve its resources. Sadly, you weren't eating ENOUGH. And to eat enough you probably would have hit that lunch budget you were trying to save in the first place. So, yes. Starving yourself while trying to do the right thing at the same time. There has to be a Greek tragedy about this somewhere. Or a maudlin French poem. Or an O Henry story.
I'm curious WHY you started having those issues. There shouldn't be really anything in sardines that will cause issues like that, unless it's all that you ate?