Miscarry

I know it is a sensitive subject but I'm just curious about miscarriage. Especially since I'm TTC. Does it hurt? Is it really messy? Can it happen without you even knowing? Do you have to stay in the hospital? What if you're further along in pregnancy and miscarry, do you just pass it like a blood clot? Again, I'm sorry I know this is a really sensitive subject and am so sorry for everyone who has ever experienced this! Any info would be appreciated.