My baby doesn’t like me

I’m going to sound like such a bad mom.. but lately my 4 month old son seems to favor dad over me. I break a sweat trying to get him to smile and sometimes he does a little but all dad has to do is walk in the room and he lights up and laughs. It’s hurting my feelings and is making me feel a little resentful towards both of them. I love my baby to death and I hate feeling this way but it breaks my heart that I don’t make him happy like his dad does. Is this normal? Does he really not like me as much as his dad?