Breastfeeding Question.. The "Right" Choice?

Let me start off by saying that I am a full-time graduate student with not a lot of down time. I have a 3 month old and have been exclusively breastfeeding. He feeds about every 2 hours. I rarely have time to do homework and I'm falling behind. People around me keep telling me to switch to formula, that he'll sleep longer.. I just don't know what to do. Please don't attack me or others in the comments trying to help. I know breastfeeding is a touchy subject and I'm just looking for some advice or personal experiences. I appreciate anyone who responds.