Hello everybody, its my first post here so I'm not sure if it's the right place for my question. First of all, let me tell you who I am, I'm a 21 years old girl from Algeria, English is the third language here so excuse me please for my bad English.. So my situation is a little complicated, i'm in second year in niversity I study geology yet it was never what I wanted to do. I have a big passion for physics and I wish I can start all my studies again from the first year in university just to study physics and make my dreams come true. But the problem is I'm not really sure if i can be successful in physics, I will start physics at 23 years old because I have to finish 3 years in geology. What I mean by successful is that i want to be a professor of physics, and start researchers domain and be a good physicist. Also I really want to get DhP full scholarship to study in USA or Canada, I'm not sure if they will accept me because I'll be a little old that time, maybe 28 or 29. After all, please understand me, what I'm asking for is about the career in physics only, because nothing.. NOTHING will stop me from learning physics, its just what I love to do, more than everything. I hope I explained my situation well, I'm learning English and improving myself in it in the current time. I'll be glad, so thankful and open for all your opinions. Thank you.