Some concussion specialists divide concussions by the systems they impact. Your symptoms would indicate a vestibular concussion. The vestibular processing system may need more time to heal. This could be related to Vestibular Associated Migraine.

A vestibular assessment would be worthwhile.

[I'm really afraid I'll be stuck with this for the rest of my life,]
This is a thought you should try to avoid. It creates an anxiety that focuses on symptoms. Focusing on symptoms will cause them to be more noticeable. Ignoring symptoms and dealing with them in the moment they impact you function is a better way to recover. The concussion researchers have found this makes a big difference in recovery.

I had to learn to move differently. If I am getting out of a chair, I need to split the move to two parts. I lean forward to get my weight over my feet then I stand up as a second move. If I try to do a combined move, I will experience a bit of balance dysfunction. It has been this way for decades, since anesthesia for surgery. It does not stop me as long as I do not do complex move or I stop and let things stabilize. I just finished a project on the roof. Up and down a ladder. I have to stop and set myself before stepping onto the ladder.

If you do gymnastics, you may have a hyper sensitivity to balance issues. This could make you more sensitive to any reduction.