I don't know how old you ar3 OP but i suspect as I'm approaching 30 I'll seem like a dinosaur compared to most on here, however, what age has brought me is a touch of life wisdom. It is so easy to fall into a trap of doing what your friends want you to do, doing what society thinks you should do, not doing what you want to do because of fear of the reaction of others.... honestly, when you're approaching 30, married with two adorable (read troublesome) kids, youll regret every opportunity you missed because of trying to follow the crowd.
Don't make the mistake of thinking that the people who surround you now (or at university) will be around forever. I have a few close friends that i keep in touch with fairly regularly (we fb message etc every couple of weeks) these are the friends from secondary school that i couldn't imagine my life without, yet if i see them 3 or 4 times a year, we are doing well! These are my closest and longest friends, and would be there at a moments notice if i needed them, but we each have our own lives.... none of us have followed through on what we had planned from school (although i am working on it, but its costing a fortune because of the way i have done it- instead of straight from school).
If you want to be a nurse or use applied medicine or be a refuse collector or a shoe shiner, do exactly what you want without fear of how others will deal with this. They havent got to live your life YOU have. Do what makes you happy and be your own person. I didnt know what true happiness felt like until i felt comfortable with my own mind and decisions.... it took me until mid 20s and a prolonged period of being single whilst my friends were away at uni to work out who i was a person and where i fit into the world.