Most Med Schools will say that you should have applied for extenuating circumstances at the time you sat your A2s, and are unlikely to accept them as a reason for your low A2 grades/resits at this stage, I'm afraid. You can contact the admissions teams of any Unis you are particularly interested in, but I would do this BEFORE you apply to ensure they will accept your circumstances.
However, there are some Med Schools that are happy to accept A levels taken over 3 years without extenuating circumstances. I am not sure how up to date I am, but it certainly used to be: Liverpool, UEA, BSMS, Exeter, Plymouth. Some want you to have got higher grades than you did first time round, and some (most) expect you to get A* in any subjects you resit.
I suspect you may be better taking this year to resit and then having a gap year and applying with achieved grades, as trying to research all this, study for BMAT, if you decide to sit this, keep up WE/extracurriculars, etc as well as work for A2s may jeopardise your grades again.
Good luck