If people stare at you in shock or don't believe you when you tell them that you don't iron your jeans.
If the whole concept of lighting is completely different than you're used to. (more on this later)
If the woman scanning your groceries at the check out stand asks what tortillas are used for and almost nobody around has ever heard of a burrito.
If all shops close at 6 pm weekdays and 2 pm on Saturdays.
If you have to stock up on certain food items (even in large grocery store chains) because they may suddenly be out of stock for many months at a time (or never be seen again).
If you've never had to find out the cut-off date for kids going into elementary school. (If you were born in 2003 you'll be starting first grade this fall, on September first or the first weekday thereafter, no matter where you live in Poland. Genius.)
If you've been told that it is disgusting/unnatural that in America your milk can sit in the fridge for a couple of weeks. This in a country where milk can sit on a shelf in the cupboard for up to 6 months before it's opened (UHT milk).
If a doctor's frequent response to questions posed by patients concerning details about their health is "don't worry", and there seems to be a general policy of "less is more" when it comes to sharing medical information. This to the point that it is still common practice for doctors not to inform someone if they are diagnosed with a terminal illness, instead letting members of the family know.
If you only pay for calls you make from your cell phone, and not for incoming calls.
If food made with the simplest ingredients taste like heaven.
If the pace of life is slow and steady, and you think therefore you may possibly win the race. Or at least complete it eventually.