I majored in Musical Theatre in college. The number one thing I learned was to take care of your voice and speak up if you feel like something is wrong. My senior year, I had to give up a part in a musical because I lost my voice. I was singing in a choir, a chamber ensemble, a musical, and rehearing for my senior recital. I had been taking very good care of my voice, but then my chamber ensemble went on a week-long performance with 4-5 performances a day and not enough sleep each night. I knew that my voice was struggling, but trusted that our conductor/professor knew best and pushed my voice too far. When I came back from that tour, my voice was bad enough that my vocal coach put me on vocal rest and sent me to an ENT. It turned out that between some unknown acid reflux and the overuse, I was starting to form vocal nodes. To keep from permanent damage, I couldn't speak for 2 months. Now my voice is healthy, but I learned that you have to speak up if your voice is struggling at all. My conductor/professor had no clue how much other rehearsing I had been doing and did not realize that she was overusing my voice. I could have saved myself a lot of trouble by speaking up sooner. Also, do not hesitate to get your voice checked out by a doctor if you need to. Even it seems unnecessary, it can help to just get it checked out.
Good luck with your degree! You will really love going to school for music!