Sex is getting boring...

So my boyfriend and I have an amazing sex life. He's always been super attentive and generous. But lately sex just hasn't been all that great for me. He just isn't getting me off and doesn't seem quite as interested in getting me off as before. We're having some other issues right now and part of me thinks this is part of the problem. We're not talking about our issue right now and can't until we know more about what's going to happen with school. So I just don't want to bring up another problem in our relationship when I feel so shaky about us right now. Does anyone have any tips on how to talk to him without making it feel like a problem? Or maybe ways to spice things up in the bedroom so I don't have to talk about it? I know that talking about it is probably what I should do but I don't want anymore problems between us right now.