While I also prefer a female doctor (because i feel more comfortable talking to another woman) your concerns about "A man sticking anything in her" are a bit misdirected. this is a doctor not a sexual practice and you should by no means feel threatened or jealous of the situation.
1.
http://skelbimas.lt/asirtu/archive_en/gynecology.htm
2. i've never had it hurt though some women do experience some minor discomfort.
3. ~20mins
4. they doctor might be willing to allow you to come along, and while i admire your efforts to support your girlfriend (And encourage her to go to the doctor, good boy!) she might want to consider going in alone so that she can establish a relationship with her doctor. it's important for her to feel comfortable with the doctor and (scary as it may be) she may be more easily able to do this in a one on one situation.