Brake fluid is hygroscopic meaning it absorbs water whether the car is running or not. I typically would recommend a flush around every 2-4 years just to be on the safe side but I have seen people go 5+ years without replacing their brake fluid. In my opinion you should either get a brake fluid tester or have a mechanic test your brake fluid for moisture. Any more than around 2% water in your system and I would flush it just to be on the safe side as your brakes are the only that stop you and thus are a very vital thing to keep in pristine condition.

it seems too early. A good shop should have a tester so they can show you exactly if it needs changing. Only takes a second.

Once every 5 yrs is good, Toyotas can go even longer