IMO, I'd suggest the gap year option tbh.
I got rejected for all my x4 medical applications, decided to do biochem and go down the postgrad route.
Having got my A Level results, I requested to drop out of Biochem and start 1st year Medicine, after I completed my first year of Biochemistry (I don't know if you can still do this)
Having been exactly in your position, and having chosen the Biomed route in your scenario, I would go back and do the Gap Year. I loved halls, I enjoyed my first year, I made new friends, HOWEVER it was a wasted year, and it messed with my Student Loans funding.
This is a tough choice for you, long term view I'd argue you are better to take a gap year, do some voluntary work, First Aid training etc. to boost your personal statement and then apply for Med. This is so much simpler regarding SLC funding.
However, if most of your mates are also going to university, i wouldn't blame you for wanting to do the same.
All I can say, as someone who was in your position, is that having done it, I would go back and do the Gap Year.
But it is YOUR choice, not your parents.
Feel free to message with any more questions.
Its a difficult decision.