Hey there Tazzaras,
I had the same issue with being shy with patients when I first started working at the office I'm currently at -- and I believe my optometrist may have mentioned it in the letter of recs she sent, although I'm not 100% sure.
In any case, what you have to do is basically prove it wrong in your interview. It never actually came up in my interview, possibly because I was able to show that I was very outgoing by being very personable. A definite thing you will want to include in answering the actual question when asked about your shyness is to say that you, yourself, are well aware that this has been a problem that you've recognized in yourself and have been working proactively to overcome it (this is something you really need to start doing, in fact, because it's true that you need to have a degree of openness in your personality as a health professional).
Even if the interviewer never ask you about the shyness, and they ask you to list strengths and weaknesses -- make sure you include it in your list of negative qualities (but don't forget to add that you're working on that problem), this will show that you know about your weaknesses (as is verified by the fact that your optometrist also noticed it and mentioned it), and that you're willing to work on them.
Regarding your academics, that all depends on your situation I guess. If you've gotten yourself involved in many extra-curriculars and they took a lot of your time, then perhaps your record doesn't reflect your potential in academia. Make sure to add something about how you're going to be prioritizing your time while in professional school (as opposed to how you did in undergrad). Anything further on this topic really depends on how good your academic record is, really. Sorry I can't help more on that point.
Good luck with your interviews!