Do what you feel is right for you.
Obviously your parents and boyfriend are going to find out if you opt for adoption-- you're going to have to endure a lot of heat if you go that route, from your family and your peers. However, most families do come around and will be supportive (maybe they would support your hospital fees, maternity clothes?). However, you might get too attached, and if you raise the baby yourself you might need to drop out of school, get a job, pay for diapers, formula, doctor, etc. There are also increased risks associated with having a baby at a younger age.
It sounds like you are not in a good state to raise a baby-- mentally or financially. If I were in your situation, I would probably opt for an abortion, the sooner the better. However, you should consider telling your boyfriend before you do anything... he can provide some support.
You might also want to re-consider what kind of birth control you were using, if any.
PM me anytime.