Need relationship advice

Soo.. i've been with my boyfriend for almost 2,5 years. Lately I've started to feel that something is off between us. If I text him, I'm lucky to get a respond within the first hour. He rarely answers my snapchats and he is shutting down when he is with me and has stopped telling me about his feelings. He could go on and on about his feelings at the beginning of the relationship and it just kinda stopped. Should I do something?