Understanding Hepatitis B: Causes, Symptoms & Vaccination

Question
My 19 year old sexually active sister has been extremely ill lately.  She has had one infection right after the other.  She has had sinus infections, strep throat, stomach bugs, just everything you can imagine.  So recently her doctor did a blood work up on her to test for STD's and other things and they found that she has Hepatitis B.  Which they then said that her test would show positive for that if she had been innoculated for it, which she has been.  However, she has only had 2 out of the 3 shots she needs for that.  Is it true that she will get a positive test result for Hepatitis B if she has been innoculated?  And if so, could she still have the actual virus if she was innoculated?  And is 2 out of the 3 vacinations enough?  Thank you in advance for your help.  

Answer
Is it true that she will get a positive test result for Hepatitis B if she has been innoculated??
Yes, she will get a positive for Hep B antibody

And if so, could she still have the actual virus if she was innoculated?
Not if she has a positive antibody level


And is 2 out of the 3 vacinations enough?? not for long lasting protection.