You know pizza isnot good for you, yet you eat it. Well expect your body to react. Smelling bad is all about eliminating toxins. Some toxins can only be eliminated through the skin pores so expect a lot of them to come out . Most deodorant contain aluminum - a heavy metal which produce the best environment for candida to strive (http://www.renaissancemama.com/how-to-avoid-heavy-metals-in-deodorant/). Pizza and deodorant are not good for you.
2- You say: "Of course it could be the cheese (dairy) and not the bread, but I doubt that."
Well it could also be both - it could be the tomato sauce, the too fat meat. Actually there is not much in a pizza that would be allowed on a candida diet. Still you want to see what YOU personally react to so the only way to find out is to eat food you tolerate with cheese and watch for reaction. Do it again with tomato - and again with the sausages to identify your food intolerances - bread is out - of this you may be sure.
3-Assuming this has been going on for years, I may have damaged my internals. What can I do?
First listen to your body and avoid stuff that is not good for you.
If it is indeed candida, the best thing to do is to be on a paleo diet. AND identify whatever specific food intolerance you have like I described above.