Help! My Puppy Woke Up From A Nap And Was Very Aggressive And Afraid!?

I have a 13 week old cockapoo puppy who woke up from a nap late last night and totally panicked. I was standing about 6 feet away from him when he woke up with a start, and ran to the corner of our bedroom alternating between blood curtailing screams and growls directed at me. He also smeared a bit of poop over the pillows as he ran. It took him about 20 seconds to calm down, and then it was like a light went on in his head. He abruptly stopped screaming, and came running towards me shaking. He then hid under my legs for about 10 minutes. I tried to go to sleep about half an hour later, but he refused to lie down. It was as if he was on guard. We were up for at least 3 hours trying to get him to relax. Before last night we had never had a problem with him going to sleep.
He is the sweetest puppy normally, but last night I was truly afraid he was going to bite me. This happened once before, but to a much lesser extent. He woke up from a nap and screamed, but it only took a few seconds for him to calm down and come cuddle me. I don’t normally have a problem waking him up from naps. I call his name and he opens his eyes, tail wagging, and wants to snuggle. I have only used positive reinforcement to train him, and he is very cuddly with me normally, so I know he isn’t actually afraid of me. It seems like he forgets who I am…
Has anyone had any experience with this type of behaviour? Is it possible he is just having really bad dreams and he will grow out of it? I am at a total loss as to what my next step should be and could really use some advice!
Thanks so much, BP

My Little Pup Is Afraid Of The Rain…?

I have a 14 week old cockapoo and he refuses to go out! We are still in the process of housebreaking him and this is totally throwing off our training! He will go on pee pad so I’m not worried about him making accidents but I want to be able to take him out. I tried treating him and introducing him to rain very slowly and he just won’t do it. I live in Chicago and if he is so scared of rain, I can’t even imagine how he’d react to snow!!! Help!