Typically in scrum environments the collection of tasks scheduled to go into a sprint in the sprint planning meeting should be considered fairly "fixed". That is, once the sprint starts, the work agreed to shouldn't change, otherwise you run the risk of having work not get finished in the sprint, you create distractions, etc.
My question though is what about times when a developer takes the initiative to (on his/her own spare time outside of work) solve a ticket that they feel passionate about. Should that ticket be considered as part of the sprint, or should it be left out?
Context for my question: I'm a developer and over the weekend was spending a bit of time looking at our backlog, and stumbled across a couple extremely small tickets. Since they were trivial (combined the two tasks took less than a half hour) I just did them. Now, should those tickets be considered part of the current sprint for reporting purposes, or should they be left out?