If you're trying to do all that, then I'm afraid you'll either piss your girlfriend off, have a nervous breakdown, or just not be able to run the service. You need more time than that.
Also, A dedicated server is not the way to go if you know how to configure it, or if you have a programmer to help you out. Go with co-location if you're serious about this. That means spending $1000 on a decent server and hosting it in someone's office. Over long term that will save you money since you aren't using their hardware. If you're just developing your skills, this might not be the right industry to do that in. Your customers are all going to want super-reliable hosting from someone who knows how to do everything in the industry. Since you are still learning, sooner or later you WILL make mistakes and have a lot of angry customers. Just trust me, I've been there a few times.