Going From Merchant Navy Training To Royal Navy

Hello everyone,

I have quite a big decision that I need to make soon. I have been wanting to join the Royal Navy for quite a few years now, but recently failed my medical at the beginning of this year due to an ingrown toenail. Because this took a while to heal, I ended up starting a course to train as a deck officer with the merchant navy. However, having almost completed the first term, I am finding the acedemic side quite hard, and the maths is very tedious to me. I have been thinking about quitting to join the Royal Navy after I have short courses out of the way with, but I am worried this will hinder me during the recruiting process. Any suggestions?
Well I was thinking officer, but seeing as though I'm struggling with it now, I'm thinking of rating instead. Was considering Royal Navy Police too, but I don't know if that would make much of a difference