What size diaper is your baby in?

My baby isn’t even 2 months old yet & she’s in size 3. 😳 She is not even close to being 16 pounds yet. We use the pampers pure diapers, & they are super tight around the legs & really short. Like the barely cover her crack. I tried using the honest diapers size 2 thinking maybe it’s just those kind but the honest diapers were even smaller! She was only in newborn for a little over a week, size one for 3 weeks, & size 2 for almost 3 weeks. I feel like that’s so fast!