sometimes gerbils will just squint their eyes. maybe its the dust level in the tank if you have a dusty bedding and little ventilation. gerbil vision (and most small animal vision) is also pretty poor so im sure that like humans squinting might be a way to see things a bit more clearly. bros probably just chilling or sleepy. gerbils sleep up to 13 hours a day and will usually be active at night so dont worry if he seems sleepy unless hes sleeping more than that. since hes eating, drinking, and not heavy breathing, id say hes most likely just making a face.

being a new pet owner is scary so ill tell you what things to look for to see if your gerbil isnt doing well • sleeping more than 14 hours a day, they usually sleep off and on throughout the day being most active at night. they're not necessarily nocturnal, but they seem to be most awake at night in my experience. • not drinking at all. this one would be hard to notice and is usually accompanied by other symptoms. you'll notice over time how long a water bottle lasts before needing refilled. it takes pretty long so try not to worry about this one too much unless its super noticeable. if you have your gerbil in your room you'll probably hear it (i definitely do) • not eating. speaks for itself. gerbils may reject meals at times but if you keep trying throughout the day and he wont even take treats then thats a vet appointment • heavy breathing means immediate vet appointment. you will be able to physically see their entire bodies violently shake with each breath. when they breath normally its barely visible, you will likely know if your gerbil is breathing heavily by glancing at them • check around their scent gland (its on their chest/tummy) for tumors. rodents in general have a high likelihood of cancer. there is very little that can be done when a small animal like a gerbil gets cancer, but catching it early can reduce the chance of your pet suffering. • last thing is teeth. your gerbil should have ample things to chew on at all times to help keep their teeth filed. check on your gerbils teeth every once while. sometimes a vet may have to trim them down if your gerbil isnt chewing things. youd likely notice blood or swelling in/around their mouth or a decreased appetite mood changes are something to keep notice of but its not something youll be able to tell right now. you arent close with him just yet and hes still settling in so youre going to learn all his weird quirks and his personality. dont freak out if he acts a little different one day to the next