I had a trach shave on the 6th of January. Since then, it's swollen up quite a bit. My doctor said this is normal, and that as I do more it might swell more, but they told me to wear a special neck thing and also massage it to reduce swelling. The swelling doesn't seem to be going away. I'm really worried this is permanent.

At about 20 days post-op, I'd be expecting any swelling to be very minimal. The fact you still have the amount of swelling you seem to is a concern to me.