welcome to nursing school, andy! no, you weren't supposed to learn about these diseases in a&p or micro. you learned about the normal anatomy, physiology and microbiology. now, you have to take that information and use it to apply to pathological situations. this is the pathophysiology of diseases. some schools go so far as to now require a class in pathophysiology. my school years ago didn't. it was incorporated into our nursing studies. you need this pathophysiology component, however way you come by it, to help bridge your link and understanding as to "why" the doctors and nurses are doing what they are for the patients. it helps to rationalize why the docs are ordering the tests, drugs and treatments and the nurses are doing the interventions they are doing. this is why there is so much studying to do in nursing school. there is so much to learn!
if you have a medical dictionary, like taber's or mosby's, keep it at your side while you are reading your nursing textbooks. that's what i did (and that was 30+ years ago!) because i ran into the same situation you are finding yourself in. dyspnea will be in the dictionary and defined for you. it's also a term that will become very common to you.
i'm sure you must have seen me post these before, but you can use these sites to get information on diseases.
don't freak out yet. save your freaking out for when you really need the energy for it. just kidding! didn't mean to scare you!