Hi Robbie. It doesn’t look like blood to me but it’s hard to tell- main thing is, as Elusuve said, just keep an eye on him and check no signs of blood on him. He sounds like a chewer! I haven’t heard of a hamster chewing a bendy stick bridge before - but some hamsters will chew anything! The only thing to be cautious about there is - they contain wire to make them bend and if he chewed right through there may be the odd sharp bit inside. It probably doesn’t say what wood it’s made of does it? When you got it? Cedar is the one to avoid and that can be a reddy brown colour.
Main thing is that Cookie is active and healthy

. Don’t be hard on yourself as they don’t like being cleaned out a lot. Spot cleaning now and then can keep on top of things - ie taking out a handful or two of soiled substrate and replacing it with a clean handful or two and mixing it in - it’s only really the pee area that needs it. They are very clean little things and groom/clean themselves thoroughly. It’s just their pee that’s unhygienic and you’ll know when that needs doing as it will smell!
Our Syrians pee in a litter tray with sand in it! Then it’s really easy - you just empty the litter tray once or twice a week and the rest of the cage stays clean and dry. Don’t worry about poops unless they start taking over - and then they can be spot cleaned out. Hamsters are corophagic - meaning they sometimes eat their poops! Which is normal - they have two stomachs and can redigest nutrients from their poops. Probably hard wiring from when there’s a shortage of food in the wild. The poops aren’t really dirty and don’t smell - they are like little firm seeds almost.
How did Cookie react to his cage clean?! When they get used to it they can approve as long as some things still smell familiar. So for example I don’t throw away the nest (unless it’s pee’d on) and try and save most of their dry hoard - the top part is usually ok (unless pee’d on), if you do have to remove it then it’s best to put a handful of new food back in the same place to replace it or they can get anxious if their hoard is gone.
Not sure which bedding/substrate you’re using but if it’s wood shavings you need to check what it says on the packet. Cedar is a big no no. Sometimes it just says “softwood shavings” and then it could be anything so best avoided - if it says pine shavings then it needs to say they have been kiln dried or dust extracted otherwise they are not safe really - softwood gives off phenols which can affect a hamster’s respiratory system. Cedar has the most phenols. Pine has a lot less if its kiln dried pine.
It’s nearly Spring now so hope you get to do some nice things and feel better soon
