why give up on being a doctor...if you really want to do it then do it! it all really depends on ur resources and if a mahram is willing to move with you to a muslim country. I think it is common knowlegde that there are MANY female doctores in saudi and they all wear niqab and have speacial gear for niqabis.

Sister we need more women doctors!

oh subhannallah sister- I was sick to my stomach just listening to this hardship. alhamdulilah, you were able to make it through, and you have made a decision based on your feelings, regardless of the pressures from the outside world. May Allah reward you for your struggle ameen