Congrats on your little one! My suggestion- box up the clothes and hang on to them for dollie dress up (as suggested previously) and if you are having more kids, you never know.
My first was 4 weeks early- total surprise. Had to run out and buy preemie everything. He outgrew them quickly... and then I donated everything to the hospital where he was born in case another mom might need them. I did everything different for my second and guess what? Five weeks early though he was good size (just under 6 lb.) and we had to hit the stores again for preemie clothes. We were blessed both kids came home with us from the hospital no complications.
Anyway, put them in a box and save them "just in case".
Have fun with your daughter. :)