Only you will know if alcohol made things worse for you. I've known some people with PCS who have drank with no problems, and others (like me) that it completely destroyed even after one drink.

I personally don't recommend drinking while in recovery. I think minimizing things that will negatively effect your brain is your best bet. You can start by reducing stress and anxiety caused by wondering if you've caused permanent damage. Stress and anxiety are your worst enemy.

If I told you that I doubt you've caused any permanent damage by drinking, will you go out and drink again?

I wouldn't do it...and no, you didn't cause any permanent damage or inhibit your ability to recover.