There are certainly several different explanations for what you are experiencing.

The condition probably has a medical origin, but I hope you'll keep your mind open to other possibilities.

Perhaps, for whatever reason, you now possess a different level of awareness than you did before and you are now perceiving things that other people do not see yet are nonetheless real.

It might be scary, but try to limit your emotional reactions. Try to understand your perceptions with some objectivity, if possible.

Of course, you should pursue whatever medical advice that you feel is worthwhile.