Why do i want to do this?

okay (im a girl) and i went to my friend annas house.....we were tlkn bout our crazy dreams of makeing out with other girls.....well we both had a dream about it so we told each other....well that night we was laying in bed watchin tv with the lights off and she put my arm over he stomach an was holdin my hand an i thought well shes jus being nice....next thing i kno is that we was making out for a super looonnnggg time....an i felt really attracted to her....well lately iv been wantin to kiss her again and do other sexual things to her.....why am i feeling this way?.....why do i want to do this???