Do I dispute my grade? (Difference between a first and a 2:1)

I'm 2 modules away from a first, this is one of them. Single semester module, assessment worth 100% of grade and 15 CATS. I received my grade back today of 52%, usually I average around 70%. Portfolio assignment, 3000 words split into 4 parts, a movie critique, self reflection, blog post, and lit review. My module attendance is not great as I've been working full time since summer (retaking these 2 modules, part time SFW is about 2k every semester). For the self reflection (200 words) I had to talk about the class I attended, and used a similar topic through a post-colonial lens for my lit review (1000 words), however since I used the same topic in both, and seperate topics for my other parts. Due to using the same topic (Northern Ireland) twice I've been given just over 50% as I haven't met the requirements of an "analytical account of power and social change in the globalised world" - I'm struggling to see how a self reflection on how I engaged in class and a separate lit review on post-colonialism on the topic discussed IN class has led to such a low mark. I was also marked down for not including seperate reference lists for each section, and not including which lecture I am referencing in the section titles, despite this not being stated anywhere in the submission requirements. I was on track for a first before this, and not sure if it's worth challenging

I don't think this is worth challenging. It's quite possible that expectations like not using the same topic for the self-reflection and the lit review, "including seperate reference lists for each section" and "including which lecture I am referencing in the section" were all specifically discussed in one of the (many?) lectures you didn't attend.
Can to get your weighted average back up to the magic 70% by doing really well in the final module? Or does the maths make this impossible now?