Bro I hate to say it but honestly you know you shouldn't even have to ask that question. Doing something in such an explicit manner at the point where you two have only been together for a matter of weeks is just a huge turnoff for the girl. It will not make her more interested in you or happy with what you guys have going. There is no real reason for you to do something heartfelt this soon...save the poem and sappy stuff till after she is telling you she loves you and is crazy about you and you play the laid back funny type with her. Then out of the blue hit her with something that tells the same message and act like it was nothing. And im talking long time down the road here, i wouldn't even consider doing something like that till she is starving for attention in that manner and is doing tons of things for you. That sort of thing means a lot to a chick after she totally is into you. As for now you should just be concerned with making her laugh, being a lot of fun to be with, and showing her times no other guy can offer. That will matter more to her at this point then any poem would, and it will keep her coming back for more everytime. Good luck guy and brush up some on the bible.