Love my bf but need some alone time

I really do love my boyfriend, but we spend so much time together and he stays at my place most nights, I’m starting to crave some alone time. I am someone who needs a lot of time by myself, but I’m wondering if I should start worrying about this. I feel bad because he’s noticing that I seem annoyed but it’s really not his fault. Is this normal or should I start to question the relationship?