Mine is! I have a pretty large coach diaper bag and it is totally full. I wish I could take stuff out but I feel like I use everything in it!
I carry:
Changing pad
Wipes
Diapers
Aden and anais blanket
Nursing cover
Burp cloth
Extra outfit for LO
Extra nipple for medela bottle
Sometimes a bottle of breastmilk
My wallet/keys/sunglasses

That's a lot of stuff! Is your diaper bag completely stuffed?