Is it worth another shot?

Hi,

I achieved BCD in my A levels this year and got into my insurance choice university but have decided to defer a year. However, the more I think about it the more I feel I would like to resit this year in order to try and get into the University of Southampton who asked me for BBB. I am planning on resitting the D as I did much better in my AS and am confident I can get this up with just a bit more practice. Also, I just missed getting a second 'B' grade by 10 UMS in Government and Politics due to me having a really bad exam. I believe the B is very achievable due to me already having an A grade in my AS year which contributes. I have spoken to my teacher and we are both in agreement that I could do better. I can't help feeling like I'm crazy for wanting to resit though as I already have a place at uni 😞 any advice would be appreciated as I can't seem to get out my own head at the moment!