How to manage sudden intense body odor?

Hello doctor,

I have a sudden intense body odor, and it is far from the body odor I normally get. It has been five days, and I tried everything, but it is so hard to remove. Right after the shower, the smell would immediately come back, plus the smell was only on my left armpit. This has been going on for five days now. I am 18 now, but I am able to manage it with deodorant and proper hygiene. Yes, I do have hyperhidrosis, and normally, it does not have a smell at all, but to my surprise, when I smelled it, it had this tangy sour smell, far from the body odor, I normally get whenever I skip a day to shower. Another crazy thing is, that it only smells on my left armpit, and my right one, which I am more active (because I am right-handed), and does not even smell. I tried to resolve it with antibacterial soap and wash. I even used Betadine skin cleanser, but just after a second, I got out of the shower, it immediately smelled. It is just so bad. This is really stressing me out. I have been absent for three days straight now because of this, and it is still not gone yet. I saw some posts and stuff on the web that sudden changes in body odor might be a sign of breast cancer, and it made me anxious. I really do not know what to do right now. Classes resume next week, and I want this completely gone before I go back to school. These are the possible factors based on my personal observation. I am pre-diabetic, and lately, I am digesting a lot of sweets. My period just started a few days before it happened, and could be a hormonal change. I added something new to my shower routine that day, which is baking soda with water, and I put it on my underarms, a lot more on the left because my right armpit has rashes, and I tried to avoid it. It is never this bad normally. If I stink, it smells like onion, and if I shower and clean with antibacterial soap plus deodorant, the smell is gone instantly. But this one is insane. I tried everything, yet the smell was still there, only on my left armpit. Seconds after showering, it will appear. If I only tap my pit, the odor will linger. I take iron, vitamins, and collagen supplements. I have low red blood cells, and I am prediabetic too. I think I may have PCOS because I have a really irregular period, but lately, the gaps are not that bad, like maybe two months compared to before, which can last more than three months. I have taken Clindamycin, antiperspirant, and deodorant advised by my dermatologist. I have done a test for thyroid because I went to a general doctor with the same concern, and told me my excessive sweating could be hyperthyroidism. I have done three tests, one is above normal, but she said I do not have hyperthyroid, though I still need to monitor my sweating, still. I have done other blood tests too, and that is when I found out. I am pre-diabetic and have low red blood cells. Please help.