Yorkie freaking out when I get in shower?

My 6 mo. old male Yorkie starts freaking out (flailing around, barking, trying to bite) when he sees me go to take a shower, he has even jumped in the shower if I leave the door open. Its like he wants to be in there or he doesn't want to be away from me? He only acts this way when he knows I'm about to take a shower, never have biting problems or anything like this otherwise. Not really sure, anyone else have this problem with their Yorkie or dog?