Hey, everyone.
Hi. At my med school (not Lodz) we have a few african americans and more than a few muslims. We get along and there's no discrimination from the teachers or society that I have seen. There are few blacks living here so maybe you'll stick out a bit if alone but in my opinion you should not let that hinder you: you will, anyway, spend 95% of your time at school / library / with your classmates.