The dog could definitely have spooked him. Also, I would let him settle in for another 2 weeks before you really start handling him. Let him get settled and get at least another meal in him. As you said, he has to get to know you and you him, but if he's spooked just about a new place and settling in, that might make that more difficult.
I would still recommend hook training, or something similar. I'll put the link to the thread I started on hook training at the end of this post.
Boas are a great and rewarding species. There are plenty of boa people on here who can help you with your boa questions. Just ask. Oh, and yes, their strength is shocking if you are used to smaller snakes and less muscular snakes.
Keep us posted and good luck.
https://ball-pythons.net/forums/show...ead-with-Video
P.S. You don't need the night drop in temps.