Hello everyone! Can you please tell me if diarrhea is normal during…

Hello everyone! Can you please tell me if diarrhea is normal during teething? Some people say it's common, others say it's a myth. I can't figure out what we got caught on, or maybe it's on the teeth. The bacteria set has always helped in such cases, but it doesn't help now (we've been dealing with it for 4.5 months). The teeth look like this.