"Basically what would be best for acute anxiety relief in moments where your thoughts start to get out of whack and you may have a panic attack?"
Great question and unfortunately there is no one-size answer. There is a lot out there about cannabis quelling anxiety and it is true that a large percentage of people who seek cannabis do find relief with it for their anxiety. But that said, it can go the opposite way with a strain that is too high in THC or if your THC tolerance is very low, which mine happens to be!
I am going to steer you towards an article that we wrote. I like this particular one as it focuses on high CBD strains. CBD is known to be more calming.
I am not a doctor and this post is based on my experience and opinion only.
I hope this helps!