I find the game to be pretty hard if I'm not paying a lot of attention to where I am. I just hope to see some black smoke to follow but if I get seen then it doesn't matter where I'm going because I'm just running. It seems like the robots have quite a free reign in where they go so they're regularly not where I expect them to be if I'm going back the way I came which ends up with me running and getting lost again.
I can usually tell that I'm feeling down when I just feel tired all the time. I start to lose concentration on things and feel like I need to go to bed, and find it really hard to get up in the mornings. Sometimes sleeping for 16 hours or so.
It doesn't even feel directly related to it when I'm sleeping, but I just realised it only happens when I'm feeling down so it must be the same thing.
I don't know what the normal price for PS+ is in your region, but PSN has a deal going on right now if you spend $50 (the PS+ sub price here) you get a $10 credit on your account, so 20% off the regular price, I always renew mine when they do this promo.
I played through it yesterday and I agree that it is amazing. It's their best game so far by my reckoning, and Year Walk and Beat Sneak Bandit are both really fantastic too. Everyone should buy this game immediately.