Dear Tan,
What you’re describing sounds like what we call a globus or sensation of something in the throat. There are various causes and indeed, it may be due to the recovering sore throat that you felt after GA, since it seems to be a new problem and given your recent history.
Other common causes include post nasal drip or reflux . I would advise you to watch it for now if it is not causing you too much discomfort, difficulty breathing, eating or speaking.
However, if it persists , it would be advisable to see a doctor or even do a nasoendoscopy (can be done as a quick bedside procedure in a clinic by ENT Doctors) to have a look. Just in case there are dangerous causes.
Hope you get better!