Is this normal? Will it pass

Idk what to say but lately I've been not so hot about my relationship with my bf. I love him and I don't wanna lose him or break up. But for some reason sometimes I question if I really want him or not. Sometimes I just don't feel right and I question our Compatability or whether or not we will make it and these thoughts will just hit me out of no where. I was just so in love with him recently and now I just haven't been feeling it for the past three days. Idk why I feel this way because he's really great. I just wanna know if this is normal doubts or its something serious. It just makes me feel bad because he's always 100% about me.