I've had similar issues with a small pocketbook (slightly larger than a ladies' wallet, smaller than a normal purse). Many FAs are fine with this item in my hands or placed next to me in the seat during take-off and landing. But I've also been reprimanded about the dangers of a carry-on item improperly stowed. I don't feel particularly comfortable putting a loose pocketbook (or unprotected laptop, for that matter) in the overhead bin.

In a pinch, I've sat on it or otherwise concealed it with my body. I figure it will only become a danger when my body is also flying through the cabin!