Boyfriend troubles, need advice

Hi I'm 15 and I'm having a problem with my boyfriend. Before I start I want to say please don't tell me that I'm too young and I cant know what love is yet because it wont change how I feel. We've been together for over 7 months now and it was all going perfectly until about 6 months. We've had a few issues but we've got over them, but now its come up that I don't show him that I love him so he doesn't believe me. We got gcse results yesterday for English and maths and he wasn't happy with his, but I wasn't there for him when I should have been and I feel so bad about that now. I love him so much and I cant lose him but unless I think of something that I can do to prove to him and show him how much I love him, we'll break up because we cant keep this up as I'm a bit difficult. the problem is that I don't see him much at school and we don't see each other enough as well, so I've already decided that I don't care what anyone else thinks anymore and I HAVE to go over to him a lot more if I want to stay with him. I just need something else to show him how much I love him because he already asked for that I just haven't properly done it yet. I'd really appreciate any suggestions, and any answers that could help me, especially as I know that's a lot to read and understand. Thanks