Because of the skyrim Bug I am unable to get one of the new dog companions given to me by the dawnguard because the scruffy dog I did have one day just dissapeared from my game and every time i try and get a new one the game tells me I already have a animal companion.... sadface.... tried everything to get my invisible dog that does nothing to shoo no luck.

I was thinking you were gonna say that becoming a vampire gives you black lips... because that is what I don't like.

I really wish they would fix this. I know I could if I had it on pc but i guess im screwed for now

i feel your pain same thing happened to me.

Play Argonian.
Lizards have no lips.

What bug?

put on a mask lol

As for the missing [follower/dog/horse] problem, its probably in the last place you left it. Followers get smart and leave your service after a couple of days, but dogs and horses are a little harder to work with. Horses always show up at the stable if you're near a town, or else they're usually close by and will come to you when you either fast travel or wait.
The problem with dogs is if you tell them to sit and wait somewhere they will wait loyally until the day they die (just like Fry's dog from Futurama) and if you forgot where you left them, well...you're SOL.
This is why its always a good idea to keep very close tabs on these things. I'm always tracking my followers and my doggies/horsies. If they go missing for even one minute I know it and I immedialte search for them or else revert to a previous save. So long as you catch it early enough you probably still have an autosave where you know your dog/horse/follower is right next to you.
I realize that you've had this problem for a while though OP. Like I said if you can't remember, then you're SOL but I'm just giving you advice on how to avoid this problem in the future.
Enter cave with dog, make sure to exit cave with dog.

I left Serana behind in the cave you rescue the moth priest from, and that almost ruined the rest of the quests for me. When the moth priest was done reading the first elder scroll he just stood there holding it up like he was still reading it and nothing else happened. The quest wouldn't complete and I couldn't move on with Dawnguard. Took me a while to realize but once I remembered I'd left her behind (I thought it'd be funny if I made her sleep in a coffin and then got in the one next to her--thing is I didn't realize cancelling the command would make her wait) I went back for her, brought her along to castle volkihar, and things proceded as they should without problem.

Same problem here, can't get a armored duckin troll because of a wack ass stray dog, sad