Salaam,
Sister how do you feel about the opinions expressed. Have we assisted you in making a decision. I pray we have.
Are you limited to studying in your country of origin? Why do you not take a semester to think and research your options.
Now, I play with rules and regulations. So they won't let you wear a headscarf. What I would do is get a medical excuse. Yes, go to a sympatheic Muslim doctor and have them write a medical excuse saying you have to wear a headscarf. You can say you are allergic to sunlight. That gets them in a bind. They will have to permit you to wear a headscarf as it becomes a medical necessity. Who knows you may give other female students a way to wear a headscraf...all young Turkish girls may become allergic to sunlight directly on their hair.
It is called the non-violent path to social change.