Will minor mistakes in my bachelor's thesis harm my future career as a researcher?
I have a perception that academicians are perfectionists and might persecute mistakes like this even when done unintentionally.


I am pleased to report that your perception is wrong! Academics are human beings who tend to be rather understanding of other human beings who, like themselves, occasionally make mistakes.  In fact, if you browse other questions on this site that are tagged errors-erratum, you will find that mistakes happen quite often in academia, just as they do everywhere else.

One slightly ambiguous citation in a thesis is


not going to bar you from doing research, 
not cause for taking away your degree, and
not even cause for anyone to think poorly of you, assuming the rest of your work is good.


If it bothers you, put a corrected version of your thesis (and/or an erratum) on your personal website, just to set the record straight. (And realistically, if anyone happens to read your thesis in the future, they are far more likely to read your easily accessible online version than a printed copy in the library.)