I'm not sure what to do

I feel that you are at an important crossroads in your academic path during your first year in college. Based on my personal academic experience, I would suggest that you can calm down and try a step-by-step approach to help you to make your decision. I selected chemical engineering as my major in college and then found out that I was particularly interested in polymer science and engineering. I decided to broad my area of expertise and selected catalysis as my major for my MS degree. After that, I realized that I was still more interested in polymer engineering and continue my PhD study back to polymer engineering area. After many years, I would say that each of this step helped to shape my technical career and enabled me to go deeper in my field of polymers and membranes. For your current situation, I would believe your personal interest and your long term career goals are two most important factors in making your decision. This is the good timing for you to:

First, revisit your interest and motivation for biomedical engineering (BME). I would ask: 1) why were you so interested in BME in the first place maybe in high school? 2) are you still interested in this field in college? 3) are you particularly interested in the current research in BME or do you dislike your current research? If you dislike your current research, you can find opportunities to explore another more interesting area in BME to perform some research; 4) what are the specific concerns you have in mind? Are the concerns related to the academic difficulty of the field, the challenges for the job market in BME, the limited growth opportunities for the idea of your most interest?

Second, explore the other two areas you are considering: materials engineering (MSE) and electrical engineering (EE). I did my postdoctoral research work in MSE and designed and developed new organic and inorganic materials for different applications. If you are interested in design, synthesis, and study new materials at the molecular or atomic level and want to explore how materials behave and can be improved, you may want to stay in this area. There is certain degree of overlap in BME and MSE. You may want to continue your study in MSE, but consider new material related research that can be applied to BME. MSE will require deep understanding of the material/properties relationship for specific applications, which can be quite technical. If you are considering graduate study after college, either BME or MSE will allow you to become very technical. I am not an expert in EE field, but I would remind you that switch from BME to EE may be a larger change than from MSE to BME. EE has strong demand in various industries, offering higher job stability. You still can have the opportunity to work on biomedical technology, such as medical imaging systems and sensors. But EE is more theoretical and mathematical oriented. You may not have a lot of opportunities to connect with BME.

Third, you want to compare your interests, your long term career plan, your skills, these three areas BME, MSE, and EE, and ask some additional questions such as which area of MSE is of your particular interest? do you prefer working with physical materials, electronics, or system design? Do you still enjoy your current research in BME? BME, MSE, and EE offer interdisciplinary opportunities. For example, you can focus on biomaterials or implantable devices in your current MSE field if you are still interested in BME. EE can also overlap with biomedical applications, such as in medical imaging and bioelectronics. You can consider EE and focus on biomedical related area in EE. Both MSE and EE tend to offer strong job prospects, but BME can also have potential, particularly in the areas such as medical devices and biotech.

Ultimately, your decision should reflect both your personal interests and your long-term academic and career goals. Good luck!