Help me I don't know what to do

My boyfriend studies all the time and I barely see him. We've been going out for three months and have know each other and were close friends for three years. He forgot that it's my birthday in two days and was only reminded when I sent a hint. I asked if he could come to my birthday party and he said maybe. I almost always text him first now and when I see him at school for like twenty minutes he will be checking his watch a lot. I really really like him and he's so amazing and when we got together over summer we hung out a lot and it was really excellent but now we are back at school it's different.