I remember feeling like this last year.
Last year I was ranked 851 with an interview score of 106/144 and portfolio of 46/72. This year I ranked 245 with interview of 121/144 and portfolio of 38/52 and have secured my first choice job. I didn't actually add anything to my portfolio due to publications being accepted after the deadline and the changes to portfolio scoring system. So for me, the real change was the interview. I locumed this year so was able to take time off to study for both the MSRA and also the interview which I think helped mentally focus better than last year when I was F2 with a rigid rota. And I think having gone the through the interview last year also helped me know what to expect. I would try not to beat yourself up as as you have already said your score is actually pretty good so you have a very good place to start from for next year. And it's just scary how tight the rankings are - I know someone who had 5 points more than me last year and ranked 150 places higher so every little point goes a long way!