Why does drinking make me confident and help my mental health?

Yesterday I had my first drink in about 7 years and before that I was never a heavy drinker. Only on occasions. 3 times a year

However yesterday when I drank some vodka i felt different. I felt free. I suffer from overthinking. Therefore I stutter a lot, when I have to record my voice can’t get through it because I’m always stuttering because I’m overthinking what I’m saying and I can’t follow scripts. I’m insecure as well

But when I drank a bottle all my head issues disappeared. I spoke for about 40 minutes without stuttering. Followed the script, and I gained a massive work ethic that I haven’t felt in a long time. Mental health was no longer a issue. I was clear even though I was a little tipsy.

Why? What is it about alcohol that just freed my head. Freed my mind. I was no longer overthinking and had clear thoughts and was actually happy. Thoughts??