Can't survive gcses

So, my end of year 10 mocks predicted that I will get all A*s in my GCSEs, which I am on track to get APART FROM ONE THING
I'm self teaching the further maths AQA GCSE course to myself (I have barely started - should've started in Summer, completely underestimated the how much work year 11 would be - all the controlled assessments and revision have hit me like a truck)
I was going to get a tutor for further maths but found nothing in my area (I'm not willing to travel very far because of how much school work I have) and I might get tutoring via Skype but I think it'll be too little too late
In theory, I want to do the further maths GCSE next year but I really don't know if I'll be able to do it especially with my mocks in less than 3 months.
I feel like if I want to do well in further maths at the mocks, I'd be jeopardising my other subjects (I really want to do well in my mocks)
What should I do?
NB: I'm considering doing Further Maths A Level, but I think I'd still be able to do it with some catch up lessons even if I didn't do further maths
I HAVE NO IDEA WHAT TO DO
Would I be able to self teach myself the majority of the further maths course, and manage to study effectively for all my other subjects by the second week of december? Any advice???
Thanks in advance