Me and my boyfriend have been dating since December. So about 5months. I have never felt so strongly about someone before in my life, he's a year younger than me, and is really into music, we are both really socialy acward so it's a slow going relationaship. So my question is what should I get him for his birthday? We are 17 and 16... he is turning 17. But my issue is that I am horrible at music, and choosing music, what do I get him??

As you know he likes music do you know what types of bands he likes to listen to? If not take him out for his birthday for a nice meal or something he would enjoy

Ask him or your parents??

Why buy him something music related when he probably already has it or has strong opinions against it?
At your age, you just don't want to spend much money, and I would put effort into a handmade card with cutouts and pictures and your own art and words, something you spent time on rather than money. And something home cooked too. If you do spend money, how about something really small that he can carry around in his pocket or put next to his computer as a reminder of you? A musical note keychain or a little animal you like.