Hi, I'm growing chillies on my balcony, and this unfamiliar plant sprouted in one of the pots. It's clearly not a chilli plant, but I can't seem to identify what it is by using online guides. I'm using potting mix from Bunnings, and have no idea how a foreign seed could have gotten in there, unless it was already in the potting mix, or dropped by a bird. I live in Brisbane, QLD.
Any help much appreciated.