Weird discharge

So this happened a few years ago and I've never told anybody until now.

Well at the time I was sexual lyrics active with one partner for a couple months when one day I stared having a bad itch down there. It was sooo bad I couldn't hold back from scratching. A couple days after the itch started I started having a greenish discharge and it was real spicy smelling. This crazy itch and that smell lasted for a week then it stopped and never came back. I've gotten tested since then and I don't have anything. So I've always wondered what was that? Was it just and imbalance if hormones or a form of STD??