Hey, have you looked at bioinformatics or biostatistics? One of them may also interest you
Keep in mind that you don't need to know which way you are going to go now, and that actually seem to have a better idea than most people. If you did end up doing biomedical science and then changing your mind or vice versa I strongly suspect the skills you learnt could still provide credit and help you in your chosen study so seriously- don't stress
Have you looked at the course outlines to see what specifically you would be studying?
The application of maths and tech to biology seems to be a big area at the moment, so if you pick a medical research path learning extra math stuff in your electives may give you an edge?
Good luck with your decision
If you do choose biomedical engineering let me know because that's what I'm planning on studying