My dog has been acting very strange lately.. not sure what it is.

[Duke17]

I have a 3 year old American Bulldog, who is always loving and energetic. Last Saturday, I noticed he wasn't being his usual self. I had come home after only being away for maybe 2 hours, and he doesn't greet me at the door as he usually does. I got to the room where he always lays, and he's no where to be found. I start calling him, and I hear a noise coming from the basement. I go down there, to find him laying in our dark, cold, crawl space in the far back corner. It really freaked me out, I don't think up until this point he has even even ventured into this room. I call him over to me, and he's hesitant to come over. Finally he does, his ears are back, and he's acting skiddish. I bring him back upstairs with me, and he's very jumpy. Just really not being himself.
He's glued to me at this point, so when I go to the washroom, he forces his way in there with me. Then he jumps into the bathtub and just stands there staring at the wall... now I'm really nervous because he HATES taking a bath. I try to get him to come out and he then goes into daze almost. He's listenening to me, but seems distracted. The rest of the night he's laying in places around the house he never usually hangs out in.
The next morning I was thinking about bringing him to the vet. I go to see him and he is back to his regular self! I think ok, great ! Something spooked him, no need to worry. Maybe it was just the wind.... which brings us to today. (2 days after the original incident)
I come home from work, he greets me, he's happy, all is well. Then after dinner time I look over at his and he laying in the middle of the floor just looking sad. I go over to him and he doesn't move a muscle. I pick his head up and I notice around the base of his mouth is all wet, like he's been druling. He doesn't druel. I pat him and hang out with him on the floor for a bit and he seems unfazed. I start heading upstairs and he jumps up and follows me into the hall, then just stops and stands in the hallway... looking at nothing. Ok... very weird.. I carry on, go into my bedroom and shut the door. 30 seconds later I heard a loud bang. I come outside and go down the hall to find him standing in the bathtub again. I talk him out of the tub, and he runs down the hall towards my bedroom. The door is shut, so he sticks his nose on my door and will not move no matter how I call him, or pet him. I allow him to enter my room and he lays on the floor. Now I'm writing this... he's still laying there not moving. Everything about this is off... I made this account just so I can maybe get some feed back? I've been trying to find artlices online of odd dog behaviours and nothing is even close to what he has been doing.
I'm not sure if it's worth mentioning, maybe I'm over analyzing, but with all of these odd behaviours, he seems very alert. It's like he's looking at something, but there's nothing there. Also, he has always had this head shake like there's something in his ear that's bothering him. I've taken him to the vet twice to have it look at, both times the vet told me it's fine. I feel like when he start acting weird, hes shaking his head a bit more than normal. Someone please give me some input on their thoughts. Thank you.

[tonyb286]

This could be so many things. The one that shouts out at me is possible seizures. Not all seizures involve fitting in the common sense, some (known as petit mal) are these hazy lost kind of phases that don't last very long. It would be very helpful for your vet if you can video it when it happens.

I think firstly, you need to get a full round of blood tests undertaken, just to check everything else is normal. If those are okay, then I would certainly consider it's more likely a neurological problem - and a mild anti-convulsive medication may help.

Tony