It's possible that what you are smelling is the result of ketosis, which is an indicator of diabetes. You really should get to a doctor to see whether you are diabetic.

I have a similar problem. Whenever I have a bad cold and problem with sinuses for couple of days, everything starts to smell and even taste like burned milk, even things that are supposed to be odorless like water. Not a very good appetizer. It helps not to bread trough the nose but I can still taste that nasty flavor when food gets deeper into the mouth. First time it happened after a bad case of influenza followed by a bad case of bronchitis 10 years ago, I was afraid it will never go away. I would hate to live with that taste in my mouth permanently. What is the reason for that? Why do I recuperate and all the smells and flavors come back and the next time I get sinusitis it all smells like burned milk again? I don't get sinusitis too often, maybe once a year or once in two years, shouldn't that be enough time for whatever damage the infection did to my mucosa to heal?

Your smoking habbits when you were in Uni most likely had no effect on this situation you describe, but it did seem to make you paranoid which is common in pot smokers.