Thanks for the query..
It looks like inflammation inside mouth that can be due to side effect of anaesthesia or the medication that you are taking post surgery..
Many medications can cause inflammation inside mouth as a side effect and it can eventually lead to inflammation and burning that is Stomatitis
So once you need to consult your Surgeon and get evaluated and if it is due to any medications then reducing the dose or changing the medication can help in improving the symptoms..
As the soreness will reduce the taste will also gradually improve..
As of now you can gargle with specialised mouthwash like Magic mouthwash and do cold
water rinses or suck ice pops..
Avoid hot and spicy foods.
and take sufficient rest..
Hope this helps..