Question regarding career in Mathematics
If you want to pursue a mathematics career, the first step is to apply to PhD programs. Once you have been accepted into a PhD program, your undergraduate grades no longer matter - no one will ever look at them again. People only care about your most recent activity.

As far as I can tell, you are asking two questions: (i) Are my grades good enough to get into a good PhD program? (ii) Based on my grades, will I be successful as a mathematician?

(i) The biggest factor in terms of getting into a good PhD program is your recommendation letters. Grades are not the deciding factor. It sounds like your grades are good enough that they won't count against you. So you should really ask your professors for career advice, as they have a better sense of your abilities and they will be writing letters for you. i.e. you should ask them for suggestions about where/how to apply for PhD programs.

(ii) It's very difficult to predict how well you will do based on what you did as an undergraduate. There are people who are amazing as undergraduates and then struggle as researchers and also people who are not exceptional as undergraduates and then become amazing researchers. Of course there is a strong correlation between how well you do as an undergraduate and how well you do as a researcher, but it is not perfect. There is no way to know for sure.

The only way to find out for sure is to try!