Haha I feel you lah, congrats on baby number 5, but honestly that hormonal rush at the start is real, the dizziness and heartburn can be quite overwhelming! A few of us mums had the same experience early on with our fifth pregnancy, so you're not alone, but do check in with your doctor about the lightheadedness just to make sure everything's okay, especially since you've got four other kiddos to manage. In the meantime rest when you can and make sure you're eating something small frequently, sometimes the giddiness is just low blood sugar talking, I found that really helped me.