The only way to know if the solution you implemented was the right one, you need to review the results that highlighted the problem in the first instance.

Did the results change in the way we were anticipating them to change?

What did we achieve?

What did we learn?

What would we do differently?

The answers you give to these questions need to be considered carefully and must be documented if you wish to genuinely learn from this experience. Do not just file the document but use it to carry out further reviews - while working on this task did you discover any other issues or processes that can be improved upon?

If you followed all of the stages of problem solving then you would have been successful in resolving your problem, however there is something more important than solving the problem - Preventing it in the first place!