A joke that went too far...

My husband and I would always plan how it would be if we had a child. It was a topic that would come up every so often because we've been together for 6 years. Now that I'm 33 wks pregnant dad couldn't be more excited for baby boys arrival and I'm like the polar opposite. I feel bad because this was part of our plans yes, but I would've been just as happy if it happend 5 years down the road. I like my silence my sanity and my sleep. Everyday this app tells me I'm one day closer blah blah blah then I get depressed all over again. Everyone knows I'm pregnant and is excited, but not me. Is this normal? I'm petrified of being responsible for another life for 18+ years and sad I let this happen to myself. Idk what to do anymore it's like there's no turning back which makes me even more depressed. Is it possible to have pre-partum depression? That's the only way I can describe it