I work in marketing now; consumer, behavioural and cognitive psychology often come into play when thinking about persuading people to buy products. Human decision-making is an incredibly complex process, so being able to draw on the knowledge I've gained from psychology combined with MMS makes understanding that process easier, and also helps me to make sound, data-backed recommendations. I also use my statistics and methodology learnings to critically assess data to draw conclusions, turning qualitative into quantitative. That's a real value add to the company I work for.
In Psychology, I'd recommend evaluating what aspects make you feel most excited; keep asking yourself questions like, "what do I enjoy most about this class?", "do I like research?', "do I prefer practical application over discovering new theories?", "Can I see myself working in a lab?", or, "What do I want to learn more about given what I've learned so far?" These questions will lead to where you want to take your studies and inform on what you do with your studies in your career.
Department of Psychology & Neuroscience