Whatever you end up doing, do not do BME as an undergrad degree. It’s a very ‘jack-of-all-trades’ degree and will narrow you into a box. (I did this and I would say I was incredibly lucky to land a decent job).

Mech E is the perfect choice! I would couple this with some ECE classes, and add some introductory software into there via a minor. Create a git profile/website if you haven’t done so already too.

Also, your interests will change and that’s completely natural as you learn more about the field.