What If I Took fluconazole 150mg Tablet And It Expired 10 months Ago?

Once a medicine has past its expiry the safety and efficacy can no longer be guaranteed.
You may wish to read this: https://www.drugs.com/article/drug-expiration-dates.html

Assuming the Fluconazole is still good some patients notice an improvement in symptoms after 24 hours but for others it may take longer. Thrush should clear up in a week.
If your symptoms have not improved within 10 days you should see your doctor. The pill may have lost its efficacy or your symptoms may not be caused by thrush.
All the best.