Congrats on getting on the routine. I just passed the 12 week mark and am seeing a tremendous improvement.
Your light-headed symptoms could simply be from a lack of calories, dropping down to only 1000 calories a day is way too low in my opinion and can especially be dangerous given the fact that your burning calories working out.
You want to take supplements that will help build your immune system back up, since candida thrives when the immune system is down. I'd get on a good Fish or Cod Liver Oil and get some anti-oxidants (Vitamin A, B-Complex and Vitamin E)
I try to keep my Magnesium intake on par with my Calcium. When you have a candida issue you most likely are low in trace minerals so its best to use a good Sea Salt instead of regular table salt which is worthless. I take 600mg of Magnesium and 500mg of Calcium a day.
Also make sure all your supplements are free of the common allergens, yeast, gluten, wheat, dairy etc.
2) I'm up on the fence regarding the anti-fungal proctol. You'll find so much conflicting advice here, some say to use them, some say they're not necessary, others say they're bad because they kill both good and bad bacteria. I personally use Coconut Oil and eat 3-4 raw cloves of garlic a day. I do believe they have helped in building up my immune system, which should be the ultimate goal when healing from candida.
Also you want to eat raw garlic, most garlic pills are heavily processed and don't provide you with allicin, which is the key ingredient that does all the work in garlic. To get the best use out of raw garlic, chop it up very fine and let it sit for a minute so it can release the allicin. I sprinkle it all over my chicken or protein source and down it.
3) Again with diet recommendations you'll get a 1000 different answers on what's acceptable and what's not. I personally would avoid canned tuna or any fish in a can due to mercury which definitely plays into candida issues. Wild salmon is a good choice, as well as beef. Avoid deli meats since they're filled with preservatives and often these ingredients feed yeast. I basically eat eggs, chicken, fish and occasionally beef as my protein sources.
4) I think Magnesium dosages will vary from person to person, but try to keep both around 500mg at the minimum.