baby fever

alright alright i have baby fever so bad. im 27 and have 3 year old twins. my husband doesnt want anymore kids cause he says we have one boy and one girl so we are perfect. yes i agree we have one of each and i couldn't be happier since it took me 8 months of fertility treatments to concive my babies. but i really have been wanting a baby. yes im happy i get to sleep in and my babies are potty trained and everything but ugghhh all i can do is think about another baby. haf anyone else thought about this?