How to make more closet space?

My clothes have like practically DOUBLED in the past week. And I had a lot of clothes to begin with; they couldn't even all fit into my closet! Well, now you can imagine what a feat lies before me because I have nearly double the amount of clothes, and no space for them. What do I do? My dad says I have to get rid of the heap of clothes on my floor today, but I don't have any storage! Giving my clothes away is not an option; I love all my clothes and sometimes I re-discover old pieces.