It's possible there could be some swelling associated with the healing process. Since you can breathe and swallow without any problems, it's unlikely there's anything obstructing your throat. Anxiety can also cause this feeling, even if you don't "feel" particularly anxious... it's similar to the feeling we get when we're sad and about to cry.
You should check with your doctor, though. Since you can't check with the surgeon, perhaps you could call your primary care doctor and ask about, if you feel you can't wait until you can talk to the surgeon.
That said, if, at any time, you feel like you're in any type of medical distress, please don't hesitate to call 911 or go to the nearest ER.
I had that choking feeling on and off after my surgery. After a while, it goes away. I think it might be something going on with hormone adjustments….might be a little high or lower and you get that feeling then you normalize and it goes away. I’ve been getting it again lately however, 2 years later, which makes me think my levels are off again.
Because so many doctors like to believe that a TSH test is all they need to diagnose and treat hypothyroidism, many hypothyroid patients never feel normal again unless they are treated clinically. By that I mean they are dosed with T4 and T3 as needed to relieve hypo symptoms, without going so far as to create hyper symptoms. Thyroid med doses should never be determined based on a TSH test. If you want to confirm this, have a look at the scientific evidence in my paper in the following link.
https://thyroiduk.org/further-reading/managing-the-total-thyroid-process/
Also, to feel normal will typically require Vitamin D to be at least 50 ng/ml, ferritin to be at least 100 (very important), and B12 in the upper part of its range.