The last couple days I've been feeling lightheaded, lethargic, tired, unfocused, etc. My best guess its due to my TOM and also being low on certain vitamins on other days. I'm a vegetarian and I think I'm always low on protein and iron. Typically, my source of protein is egg whites and greek yogurt, sometimes meat replacements.

Today especially is hard to stay focused even thought I had a banana in the morning, eggs whites 1g spinach and toast for b-fast, and so far another banana.. I'm eating a fuji apple as I speak.
I don't feel hungry, but I feel like I need to feed my brain! Does anyone else have days like this? And if so what do you do? I used to have the urge to binge when I felt this way (especially when stress is added) but today I just want to focus on what I can do to get my head straight so I can get work done, go for a jog, and study for an exam!!

I already chewed half a pack of gum and drank 5 water bottles

First off, I know this is unrelated, but I LOVE the Decemberists (and the song in your signature).

Anyway, I was a vegetarian for a long time too, and I definitely remember that feeling. I used to always carry around little bags of almonds, since

a) they're high in protein and
b) they're really filling.

If you're worried about portion control (because nuts are surprisingly high in calories), a few different brands make 100 calorie packs of plain almonds.

Hummus is also good for protein, and you can dip pretty much anything into it- I eat hummus and baby carrots a lot.

Hope this helps!

Taking black cohosh supplements helps me a lot during that time

I'm not a vegetarian, but I too feel "blah" during the TOM. I'm constantly exhausted and I feel hungry all the time. Usually, chocolate is my go to savior, but I gave it up for 6 weeks and honestly didn't miss it. I have TOM now and I just force myself to go and work out, no matter how tired I am. I always feel better after a good workout and I have a trainer who gives me customized workouts each time I show up. I pretty much make an appt with him which forces me to go.

Sometimes no matter how much we want to do nothing, we have to get up and move. Same with eating - if I'm hungry, I eat, but I honestly ask myself whether I'm hungry, or I am bored. Most of the time, it's because I'm bored so I have water.