From here you have a few ways to go: 1. You can run away and try to forget about it as fast as you can. That's always a fair choice, unless the unique thing keeps hunting you down, as it often does. 2. You can ignore the uniqueness of the experience you are having and pigeonhole it into one of the groups of previously known things. You will thus have a set of false expectations and that in itself may or may not become a problem. 3. You can get angry. If the unkown thing brings discomfort or fear - you can try to scare it away, to let it know that if it doesn't stop messing up with your worldview it may be in trouble. 4. Or you can choose to overcome fear, bypass anger and focus on curiosity. You can try and figure it out. You can form a new model, test it against reality, fail and try again. You can learn. You can allow the unknown and the unexpected to enrich your worldview.