Be careful. You might have candida, but the root cause of your symptoms might be something else. Candida (if it is chronic), is often a secondary infection which takes advantage of something else going wrong in the host. For example, you could have undiagnosed diabetes, or a thyroid problem, or parasites, or mercury poisoning - any number of things including bacterial (not fungal) dysbiosis. I would advise you to get a good physician (easier said than done). Have you had your fasting insulin tested? That's a good place to start. Check for insulin resistance or even diabetes. I believe that the spit test is rubbish personally. I do have candida, incidentally. Your symptoms do sound like they could be leaky gut, but again, this could be due to parasites.
As for being tired after meals, this could be due more to a blood Sugar problem than an allergic type reaction. Try eating a meal with fewer carbs. Just have a piece of chicken and some low carb veggies or a chicken salad or something and see if you still get fuzzy. What does your typical menu in a day look like?
Do you have any swollen lymph glands?
Does exercise wipe you out? Being more physically active and eating fewer carbs or less glycemic carbs might improve your energy. What sorts of foods do you eat?
Passing stools frequently is not bad.
Don't rush into a candida cure. A candida diet can make you worse, not better if done poorly. I had milk symptoms like you, then tried to "cure" my candida and ended up getting really, really ill. You m ay have candida, but you may well have something else. Be careful.
Also, be careful what remedies you try. Like I said, I messed myself up badly. Take lots of good probiotics. That's a start. Don't eat sugar, that should help too.