do you have your gall bladder? I had a like problem, and could have sworn it was kidneys, but one thing that will feel like kidney pain, can be simple lower back pain. While not overtly overwieght , just sitting in a chair or bad bed, will make the area around your kidneys hurt, and one would swear it was a kidney problem . If you Urine is "mellow yellow " then it is not kidneys. easily could be lumbar issues.
Drink 8 glasses of water a day, not excessively if you are trying to flush them. Hydration is good for you, but it can lead to problems if you are over doing it.
The Pizza Hut, McDonalds, or fatty foods raises the question of gall Bladder or Gall stones. A Gall Bladder problem, is usually triggered by fatty foods, and can come out of nowhere. The "crunched up feeling is what you would feel if you were having an attack, as it in many instances, feel exactly that way when it beomes "constritcted". You will feel it on YOUR right side, just below the ribs, you will feel it in the back at the Kidney area , and it can shoot across your chest, toward the left side, breast area. It can affect both sides of your back.
This would be my strong bet,as I had the same problem, swearing I had a kidney problem. The foods you describe is exactly what triggers it. Diet, meaning no to low fat food, eaten more frquently , rather than at one time will tell you. Fruits veggies, Grains, yes, bland stuff. Try that and see if that makes a difference. I bet it does. If can cause the chemical rise in your pancrease, so if you drink alcohol, or have been a heavily drinker or used to , stop until you get this checked. When the gall bladder gets bad enough, you will know it. Vomiting, extreme pain etc. Removal of the gall bladder is usually the result. You don't need it anyway ..Pancrease you do, and if you have this, I would stop drinking any alcohol until you get it checked. A simple blood test and a ultra sound will tell you.
Please see Dr, it is something you want to know, but if you are not a heavy drinker, try smaller meals, more often, little or no fat. Boring I know, but this sounds more like your problem, considering what triggers it.
As always, see a Dr if you have ongoing problems. Internet can guide you to some useful info, but it cant diagnoses you . Only a Dr can do that with Examination, tests etc. It sure sounds like gall bladder or gall stones, so a simple test, and change of diet will help in he mean time and eliminate or confirm the issue. Many things can make your Kidneys feel like they hurt, but it is usually one of the above. If you had KIDNEY stones, you will know it. No doubt. Again just the mention of the triggers, they are going to look right to your gall bladder. It is actually more common than you think.