Meowing At My Bedroom Door! Help!

meowI am so frustrated with my cat. She meows constantly outside my bedroom door around 4 or 5 AM not letting me sleep well. Before bedtime, I always make sure she has her water and dry food beside her bed, her litter box is all clean and sanitized. Then why the sudden meowing? She doesn’t do it every night. But MY GOD when she does it’s so loud and annoying!
Should I just use a water spray when she meows? I have used this before for other unwanted behaviors but not the meowing part.

I love my cat, but she’s driving me crazy. She always paws at my bedroom door. If I let her in, she demands attention and won’t let me get some sleep. If she’d just settle down, I’d happily let her sleep with me! If I don’t let her in, she cries at the door. How do I break this habit?

I’m posting this because she’s been meowing now for three nights straight.

PS; My cat is spayed so she’s not in heat.