You already said that you love eachother after a month? Sounds a little bit like rushing it to me, and she doesn't seem to be in any hurry. I say just hang out and enjoy your time with her. If being in a "serious" relationship with her is so important to you, give her some more time before you ask her to be your girlfriend again. If she still says "not yet", you may have to reevaluate the situation and decide if a casual relationship is alright with you. If it is, then you're at least both thinking at the same level and I'm sure there will be good times ahead. Good luck. 🙂