[intricatic]

A testimony, I believe, is a statement of what God has accomplished in one's life. It's like a drawing, or a portrait of one's life before salvation, at the point of salvation, and the works made manifest after salvation.

I would think a fine testimony would consist mainly of what God has accomplished through you - a testimony, biblically, was something used to make a contrast, or an example of another thing.

For instance, in the first covenant with Moses, the Ark served as a testimony (the Law was laid with it to serve this end), signifying the works that God expected of His people (and would make manifest through His son, Jesus), as well as signifying God's mercy and grace. (Exodus 25:10-22)

So no, I don't think a testimony is purely about the first time you meet Jesus, although I would not say a testimony has nothing to do with the first time you meet Jesus, by any means.