OP, I'd recommend against dropping both French *and* German - uni's won't particularly like the M + FM + AFM combination as your only A2s. I'd recommend taking M + FM + AS AFM, and keeping either French or German as an A2. If you're desperate to drop the languages then you need to contact unis first.
I'm currently studying M + FM + German at A2 and self-studying AS AFM (I'm taking all the units except M3-5). Message me if you have questions about it. From my experience, self-studying is absolutely possible. However, resource-wise, there might be some issues, especially if your teachers haven't taught the more obscure units (S4, M4/5) because you'll have no-one to ask for help / to explain things. The textbooks can sometimes also be an issue - I'm on Edexcel and the D1/2 textbooks are very poor quality.