Help! I can download TV shows but I cant rent movies!

I am downloading TV shows but when I try to rent a movie it says that this computer is not authorized. It IS my 5th computer and I am out of town so I can't just de authorize other computers. It doesn't make sense to me that it IS authorized for TV shows but not movies. I am using a new Macbook Pro and I am new to Mac. I can't seem to find the place where I authorize or de authorize computers on the Mac. I am afraid to deauthorize ALL computers in my settings because I am afraid I will mess up all my devices while I am out of town for the next week. Can anyone steer me in the right direction?