I'm glad to hear that you are going to have the baby and that your boyfriend is there for you! Hang in there! The first trimester is tough. I had no energy and was sick all the time

But the morning sickness will get better. It's tough trying to balance pregnancy and/or motherhood and school. In my case as a full time grad student, but from what I remember of high school it wouldn't be any easier - perhaps harder.
Yes, there will be big adjustments and big changes in your life. You may miss out on some of the carefree times that you would otherwise have had, but you will also find yourself blessed. Pregnancy is not easy and the sleepless nights that sap your energy in caring for a newborn are tough, but when your baby smiles at you it will just melt your heart and you'll realize that all the hardship was worth it.
You may have to make adjustments, and changes to your plans but your life is far from over. Don't give up on your dreams. Like was already said keep working towards your education and striving to be the best you can.
Kate