Unknown Spotting

I found this plant in the Singapore American School rainforest with my partner. However, I was unable to identify it and it probably isn't grown fully as it is about 25 cm tall. It's leaf shape is elliptical and the leaf dimensions are 3cm by 1cm. Its leaf margins are serrulate (fine serration), and its leaf venation is netted pinnate. The leaves have a smooth texture and are in an opposite arrangement. The roots were underground.