Ipseo Welcome.
When I was a kid I made the same error. The US Administration of the Philippines made two different denominations that were EASY to confuse. They are virtually identical on one side and can be mistaken one for the other if you don't happen to turn them over. However the 5 centavo with the man's picture is copper-nickel and the 10 centavo with the Standing Woman's picture is silver. When they get dirty they are easy to confuse. But the value is quite different now that silver is up around $20 an ounce.
Like I said when I was a kid buying coins at 10 or 20 for a dollar out of a junk box I was collecting EVERYTHING I could afford. This one Saturday I sorted out Philippines coins by date and thought I had a pretty complete set. I took only one of each date and mint mark. When I got home I realized that I had both 5 and 10 centavo coins. I had not noticed I was picking up two denominations and confusing them. So I went back the next week to do it again.
Back then in 1957 silver was lower in value (under $1 as I recall)and a foreign dime sized coin had far less than 10 cents worth of silver in it if you factored in the costs of recovery. I only wish I had saved more back then.