If you had a leak somewhere in a pipe, that much water would be impossible to not see.

If you had a leaky toilet flapper valve, that could be leaking even more water than what you reported. We had a leaky toilet in a rarely used bathroom, and I was out of town for 7 days. My wife found the leak after 6 days or so, but by that time we had used 4 months worth of water in just 3-4 weeks.