I can't be sure without a link to your deleted question but yes, closed questions are deleted by the system after a while. You can see the details here, but in short:
If the question was closed more than
9days ago, and ...
- not closed as a duplicate
- has a score of 0 or less
- is not locked
- has no answers with a score > 0
- has no accepted answer
- has no pending reopen votes
- has not been edited in the past
9days... it will be automatically deleted
This is not a judgement on you, no humans were involved in this deletion. It is simply part of the automatic cleanup that is part of the Stack Exchange system.