Actually, one other thing I should mention - I started doing it, in part, because I was in a bit of a bad place at the time and figured exercise is supposed to be good for mental health as well as physical.
Tonight, walking home afterwards, I did feel really good after. Like, calmer, not so dragged down by stuff. Might just be endorphins that'll wear off soon, might be some other factors, I don't know, but it it was unexpected and noticeable.