Bed Bugs are not green.
Bed Bugs are often reddish-brown to brown in color and the color of bed bugs can also vary depending on the age of the bed bug and whether or not the bed bugs have recently fed.
Bed bugs which are newly hatched nymphs can be translucent or whitish-yellow in color and they become even more brown as they mature.
Adult bed bugs which have recently fed will appear as reddish-brown in color and the adult bed bugs that have not fed recently will be more of a mahogany color or rusty brown color.
Green bugs that are seen in homes and bedrooms are often Aphids although they can be other types of bugs as well.
Aphids are green bugs which are easily brought indoors such as on infested plants, becoming attached to your clothes, or even by the wind through an open window.
Aphids also come in a wide range of colors and not just green, but aphids can also be yellow, orange or red, beige, pink or even black in color.
Aphids love young tender growth, which can be completely covered with the insects.