Brief Answer:
May be incidental...

Detailed Answer:
Hi,

I understand you had multiple clinical condition periodically which may or my not be related to each other. Sty, wisdom tooth infection, foot wart/corn are not caused by similar causes. Mouth ulcer/canker sore may have been part of acute infection (flu perhaps). So in my opinion all these conditions are independent of each other. You can prevent them by practising good personal and dental hygeine. Washing hands thoroughly and twice a day brushing and flossing usually keeps eye, dental and oral conditions away.

Flu is caused by common viruses. You may have developed mouth ulcer secondary to infection and stress. At this point of time when frequency of episodes are not alarming I would not perform investigations to treat it.

In short, I don't think we have any cause/causes to explain all your suffering. You should maintain good hygeine, eat plenty of fruits and vegetables, get regular dental check ups, perform exercises and avoid unnecessary medications.

Hope this answers your question. Let me know if you need clarifications.

Regards

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