Let me give you a hug!
I had a precipitous labor with my last birth. It was 1.5 hours. And, yeah, if you shaved an hour off of that, I'd definitely have noticed!!!! This time I keep telling my DH that if everything happens faster or even as fast, I'm going to need some time to just hang out and finish being pregnant while I hold/nurse the baby.
One thing that I do that helps is I envision myself responding to a quick labor... what I'll do depending on if I start out grunting with the ctx or not. If I start grunting with ctx, I envision myself going straight to the bathroom (do not pass go) and drawing a bath. (I really want to get a pool thermometer & draw on there two lines at the appropriate temps to represent ideal water birth temperature, so no matter how out of my brain, I can figure out if the water is too hot or too cold... I doubt I'll be able to figure it out otherwise.) I lay on my left side in the water with my right foot propped on the soap caddy and I let my body do it's work. I place my hand on my perineum as I feel it stretch. I apply pressure if need be. I catch my baby as he/she emerges. I breathe my baby out, I am calm, my baby's birth is peaceful and gentle.
That's the script I say to myself whenever I get caught up in fear. Can I handle it? What if it's shorter?!?! What if....!?!? Is just not helpful. So, if I feel fear coming up, I'll give myself some space to imagine the birth & my response.
Do you have a copy of Birthing From Within? There's an AMAZING section on releasing fears about birth outcomes in there. Oh, man, it's amazing. Right now while you're feeling the fear intensely, I'd go get your hands on copy for sure. I think it would really help.
As far as tearing goes, upright definitely has gravity working with you for a faster, easier to push out birth. Maybe you'd like side-lying or laying down modified squat instead? Or even hands and knees? The other thing is that water really cuts down on tears. If you can get in a bathtub or spa fast, that would probably help, too. Planning to (which you know, plans do change in birth!) feel your baby's head as he/she crowns also helps slow down pushing sometimes. (Goodness, I just realized that the birth I envision uses each of these suggestions.
I didn't even plan it that way, just seemed like a good idea that I was drawn to while imagining.
Wishing you a happy, healthy pregnancy and a beautiful gentle birth no matter how short it is!