There are lots of other ways to express affection, love, and attraction without having sex. Why do you feel that you have to take it farther now? Actually a month is pretty soon. How would you feel if you had sex with him, and then next month you weren't together anymore...would you regret that you did it? Would it make you want to hold onto the relationship even if things started going bad? It's happened to a lot of girls that they'll have sex with a guy and then later find out he's not all that they thought he was, but they don't want to end the relationship because they've had sex with him, and wind up being in a perpetually bad relationship.
I would suggest that you know for sure what you are getting into, and look at all sides of it, all outcomes and whether or not you'll be able to handle them, or want to deal with them. If you are going to make the commitment of having sex, don't you think you deserve at least the commitment that he's not going to see anyone else (i.e. The commitment of officially going out?) If you already think you know a lot about each other, think how much more you'll know later, and what a better informed decision you'll be able to make.
Just on a chance, you have to realize that people can hold up pretty good facades or fronts for a month. He may be prince charming this month, but you could find out later (hopefully sooner if it's the case) that he's the player from hell, and he's tricked a lot of girls with his charm.
Just don't jump into anything. Know all of the possible outcomes. Sex is a big responsibility, actually, and people tend to overlook that part.
Pregnancy, STD's etc...We don't like to think about them, but it's a part of the decision to have sex. Condoms are good way to reduce the chance of STD's and pregnancy, but they are not 100%. Have you thought about going on the pill as well? Look into all your options.
You sound like a responsible girl, and I hope that whatever you do decide is the wisest decision for you.