I want to be sober this year but can’t help feeling anxious

I want to go into this new year fully sober, but have constant anxiety over my past. I am 20 years old and started drinking around the age of 16. I began binge drinking around 17 and it would happen around once a week. I then went into college (at 18) and would binge drink and blackout really bad about once or twice a week. This continued up until recently, even though I went the whole summer fully sober. Over the summer, I began to feel SO anxious for my actions, im sure some of you remember me posting on here. Unfortunately, when I was put back into my college environment I decided to “drink a little,” but sooner rather than later I began to go back to my old habits. I’ve been home for about 3 weeks now and haven’t had any alcohol, but im beginning to go down the same spirals from the summer. I am convinced that my health is ruined and I have irreversible damage due to alcohol. I am feeling anxious and overthinking what could’ve happened on every blacked out night from 2.5 years ago. I don’t know how to keep going like this. Over the summer, I had routine bloodwork done and all of my liver values and results were normal. I still keep convincing myself that I have brain/nerve damage that I can’t reverse. I also keep feeling like I can’t escape my past, and things that I convince myself happened while I was blacked out will come back to haunt me. I feel like I have ruined my future but an inspired by the people on this sub to keep pushing. I want to believe sobriety is worth it, but I can’t help but feel like all of the damage is already done. I truly don’t know what to do, does anyone have any advice?