Extended Medicine

Hi guys, need some help and advice
So I'm sure I want to do medicine. I've known since I was 10

I don't acedemically thrive and have been predicted ABB/AAB (maybe AAB)

Now, I want to see where I stand when applying to medicine. Of course I don't qualify for normal medicine route but have decided to apply for kings extended and Bristol course. ( will apply for 3 biomedicine courses aswell)
Do I have a chance or should I just stick to chemistry?

Stats:

6As 1a* 3B 1E at gcse
BBBCC As (all reformed except maths but got a B)
1 year at 3 different places as a lifeguard
3 months voluntary at charity shop
First aid
Level 2 in CPR
1 week hospital at kings
Football weekly, rugby, biking 10 miles weekly etc...
Will join more school clubs and make a medicine club
Still need to do UKCat but costs £80

To summarise: should I ?