Hi Jordie
I didn't even do a physics A-Level, and I only did double science at gcse level, they didn't even question the physics thing in the interview - they asked me how I would cope with the maths - I think this was because I had accidentally put music A-level on my application instead of Maths A-level - Oops!!
I still got through tho, soI wouldn't worry too much - just explain (if they ask) that if you had your time again you'd try harder...etc etc You have a degree now tho and that shows you can study to a higher level regardless of the subject, so you should be fine.