It's important to remember that weight fluctuates a LOT during life changes, like moving or changing careers and the like. It doesn't mean that you've done anything wrong...it's perfectly normal, and nothing to hate yourself over. People talk about the 'freshman 15' in college, but really, there's a 'freshman 15' for almost every major life shift.
I can't give you much advice about your exercise routine, but I find that walking really helps. For an extra exercise bonus, intersperse your walks with quick jogs before taking another few minutes to relax. Using a timer helps...just gradually up the amount of time you spend running and decrease the amount of time you spend walking. That should help build up your stamina, which might help get you back to the running-8-miles stamina that you had before. I also find that it helps clear my mind.
Best of luck!