Does it have to be about baby?

Please let me introduce myself, I'm a relatively new mom just over 3 weeks and really love being a mom.  It's everything I dreamed it would be even during the difficult times (ex: breastfeeding challenges, many diapers etc).  One thing I didn't think would be an issue was my relationship with DH.  Maybe its in my head but I'm overly concerned about how LO will impact our relationship.  At first DH was nervous about holding her, changing diapers etc but he has dealt with the fear so he has become more helpful and I have become less resentful of feeling like I'm doing it all.  Though during wee hour feedings we seem to be at each other's throat, especially when LO does that dreadful screaming that doesn't seem to end (and we're deciding on what to do does LO need a diaper change, is she hungry etc).  I understand that when under stress we say things we don't necessarily mean but I take some of the criticism personally and it's hard to shake.  DH says I'm being silly (I mentioned to him that I don't want our tiffs to lead to bigger problems, like a divorce) he says that he's sorry for the disagreement but he sees it more of with us learning the ropes, not experienced parents yet and that everytthing is fine and that I need to give myself a break (I guess I'm my own worse enemy) but I'm still worried.  Is this normal?