Everyone does their writing 'schedule' a different way. Some people do a certain number of words per day, or a certain amount of time. Some people write multiple times a day, some write less often.
I don't think there's a write or wrong way to do your writing time, with one exception. If being a writer is something that's really important to you, I DO think you need to do it.
It could be coincidence, I'm not sure, but it was only when I finally made myself put some discipline into my writing life that I got that long-awaited first contract. I have little kids--one is 2 1/2, one is 3 months old. Last summer when I decided I needed to write every day, I only had the 2 year old (haha, obviously) and initially I wasn't sure if I could write consistently with a toddler boy to care for and chance around. But you know what? We make time for things we believe are important. And I eventually decided my writing was important enough to make time for. Sometimes I wrote during nap time. Sometimes my mom came over and babysat while I took myself to Barnes and Noble and wrote there. Sometimes I hauled the computer into my toddler's room and wrote while he played on the floor. I didn't stick to my schedule perfectly (does anyone stick to a schedule perfectly every day???), but it worked much better than just saying to myself "I'll write...sometime..."
Maybe 9 o'clock isn't a good time for you. If other life activities make this time not work, choose another. If the idea of being creative and producing something half-decent at an hour when coffee has not yet fully flooded your system and your brain is barely working, choose another for sure.
But, I would say you should choose a time that works for you, a certain amount of days that work for you, and try to put yourself on a schedule for at least a week or two, just to give it a try. Maybe commit to writing at least 5 minutes every day. Or say you're going to work on your story every Monday for an hour. Just something. If you love it--great! If you don't love it because right now you have other things you have to do that make it impossible--that's fine too, you can always try again later.
Now, if you'll excuse me, both boys are napping, so I better go practice what I preached here and get some words in... ;)