I have to admit I don't know what a haw is!* Never seen it on the other 5 cats we've ever had in our household over the years.. but then I've only ever had moggies before. Are you able to tell from that photo if Logi has deeper set eyes? Again, I can't really tell! (boy do I feel stupid!)
I would imagine he is both tired and stressed as he's only been with us a month and is still getting used to Lancelot (our other cat) He did the howling non-stop thing for two weeks but that has since got better. If I ran around as much as he did I'd be tired too!
Thanks for the reply.. it's definitely put my mind a bit more at rest.

*Just looked up 'haw' and realised its another term for inner eye.. so yes.. that is the bit I mean!