What kind of facility are you working at? Hospital? LTC? SNF? In general, orientations in LTC are much shorter than in the hospital setting. 6 shifts isn't unheard of. Is the position full time, part time, or per diem? Again, per diem positions will receive much shorter orientations- even in the hospital- because the hospital doesn't return their investment as quickly.
What were you told during your job interview
? You should always, always, ask about the orientation process when you are applying for a job. Unfortunately, as a new grad, you might have been so ready to accept any job that you didn't think to ask. In the future, remember that this is an important question to ask during your interview, before you accept a position.
If you truly don't feel that you are able to practice safely at this point, approach your manager, explain the areas where you feel uncomfortable, and ask for a few more days of orientation.