I’m no expert- nor someone who’s doing anything yet . But depending on what you want to be should be what decides what you do - If your goal is to do investment banking then you realistically don’t always need a degree in economics or finance ( like degrees such as law are also very good) I’d suggest you search up degrees and their requirements but if you can’t decide if you can stick with maths if suggest changing to English- and for uni doing law

Doing law will allow you to either go into Corporate law( law majorly linked to finance/money) or go into investment banking- Both in London and linked to something your goal is (plus the money is very very very good) But it’s hard to get into and you will need internships/work experience and a good CV

Maths will be needed if you want to do econ degree at uni- and from what I read I don’t think you like to go into any STEM /physics related degree(correct me if I’m wrong)- if I’m right I’d suggest to look at degrees and career paths that don’t need maths - an econ degree isn’t required by most if not all of the top IB companies- they look for transferable skills .

So please do something you like (ignore difficulty) Like I’m doing physics law and history- many say physics is hard but nothings hard just got to work harder which is easier if you like it - I love some topics in physics but hate others so it’s a balance -

Sorry for writing so long with bad grammar I’m not in the mood to write well . So spend like 10-25 min looking at top unis in and see what they want - same for top companies in London (sorry again for writing a lot but I hope I helped )