When someone says they love you, should you say it back?

Okay…if your boyfriend/girlfriend tells you for the first time that they love you - should you say it back? If you don’t love them but you do really like them, is it best to be honest bout it or is that really horrible?

I was in the situation where me and my boyfriend went through a rough patch but we are all good now. Last night we were in bed and he said “Theres something I need to tell you” and I was like “Yea…?” and he goes “I love you baby.” Now my reaction was “Really?” and he goes “Yes, I’ve fallen in love with you.” And as I’ve never had a guy say that before, I did NOT know how to react! I felt so bad. I didn’t say it back cause I do like him but I don’t know if it’s love. I kind of giggled then gave him a hug - gah! I felt like such a b*tch. Then he goes “That wasn’t the reaction I was expecting..” and I ALMOST just told him I love him too but I didn’t want to lie…I feel like such an immature teenager even asking bout this but like I said, I haven’t been in the situation before :(