For me, I was very good at Math, but I realized it was the "solving puzzles" aspect of Math that I enjoyed the most, not necessarily the specific applications the Math was being used for.
Do you like working with people or by yourself?
I like working with people so I ended up going down the Financial Reporting rabbit hole for a company that offers services in this field. Helping answer questions about report results, prove out complex calculations, help streamline our client's processes etc
I think those two questions will help guide you the most. Is your enjoyment in Math specifically topical, and how do you SEE yourself working with Math. Headphones on, locked in, or in a room with other folks and a white board :)
You should ask yourself what you want to do for your future career. Go where your heart is, and your love in mathematics will carry you a long way.
a) Problem Solving, b) Applied Mathematics - Computational Mathematics areas such Linear Algebra, Differential Equations, etc.
There is a Computational sub-area to all STEM fields. Example, Computational Biology, Computational Chemistry, Computational/Quantitative Finance, Computational Mechanics (Mechanical Engineering), etc.
There are couple of approaches to career choice:
A) You can pick an area which covers two or more of your interests, e.g., Computational Biology - Biology and Math.
B) Pick a general area - Computational Math/Science, or Data Science and defer the application area to a choice down the road when are closer to graduating with a Bachelor of Science degree.