Should I apply to Cambridge?

I'm in year 12, studying Maths, Further Maths, Physics, and Chemistry - with a keen interest in studying physics at university. I go to an underperforming state school and got 9999988887 at GCSE. My grades currently stand at a*aa with no grade in further yet (but it's going kind of terribly - need to change revision methods!)

I'm afraid of not doing enough to prove my passion for physical sciences. I take all the opportunities I can get, but due to my circumstances being quite poor - I feel it wouldn't make a competitive application against other people.

I have:
- completed SMC, the only person to get silver (being the highest scorer in my cohort)
- volunteer in a chemistry prep lab in my school, I test out new equipment and fix old stuff, sometimes I prepare practicals for children
- hopefully will get some work experience in a materials engineering lab, will find out in a month.
- I also help tutor 11-15 year olds in the sciences including SEN children
- part of STEMSmart, I'm finding this helpful for overall confidence.
- I read a lot of articles about particle physics in particular, my favourite current physics 'news; is the muon g-2 experiment, and CERN observing how antihydrogen responds to gravity. I'm a large fan of symmetry magazine. This led me to discover the wonderful world of physics beyond the standard model, which is probably what area I'd like to research if given a choice (optics comes close second!)
- If anyone has some maths, physics, or chemistry documentaries recommendations are welcome!
- I've completed some short MOOCs about particle cosmology.
- I'm not sure if this counts but I did Salters Chemistry Fair in year 10 which was a lot of fun! I got to synthesise aspirin, then heard some lectures done by Ph.D. students on graphene filters to purify water from antibacterial medications and carbon capture technology, which sort of kickstarted my initial interest in materials and the overlap between physics and chemistry.
- any extra stuff I can do to deepen my academic understanding would be appreciated, as right now I feel like I'm interested in certain topics, but have no actual mathematical understanding of what's going on.

My extracurriculars are pretty weak. I had to stop all forms of sports and dance due to a major car accident. My grades weren't super special, G4 in ballet, tap, and modern jazz, however, I couldn't have done more if I wanted to due to the nature of my accident.
I do play instruments in my spare time, however this is casual and out of my love for music. I enjoy playing piano, guitar, trumpet, and trombone. I also keep a sketchbook, being a habit from my GCSE fine art days :P - originally I wanted to do architecture, so the arts are incredibly important to me.
I also go to a weekly youth group at church, and studying the intersection between science and faith is impossibly fascinating to me. If anyone has some good seminars on the topic I'd be grateful! We volunteer and help our local town with food banks, fundraisers, etc. but it's generally just a bit of good fun.

Despite my keenness to study physics, I feel like my knowledge and academics are weak. Seeing comments like 'there's no point in doing further maths unless you got a comfortable 9 at GCSE' is quite discouraging (even though I got an 8 which is still pretty good). My a level grades are good, being only 4 months into year 12, and I intend on only getting better.

I am looking for my insurance uni to be Imperial (due to my extenuating circumstances, I should be guaranteed a place with three A's, granted I show strong interest and do well in their admissions assessment.

If anyone could give advice, guidance, recommendations, thoughts, and opinions - all would be much appreciated

Yes, you should probably apply. Don't worry about your extra-curriculars - they are of no interest to Cambridge. Your GCSEs are fine too.

I realise it's early days yet, but you'll need to get those A level grades up. The minimum entry requirement will likely be A*A*A.