Am I unable to do so due to only having ~900 rep on the site in question?
You can only see deleted questions (that aren't your own) with the Access To Moderator Tools privilege (10k on graduated sites); otherwise you're out of luck.
You can see reputation changes from deleted posts under the reputation tab of your profile, just make sure "show removed posts" is checked and look for anything with the "removed" label. If you have the ability to see the relevant post then the title there will link to it—so look there first.
The only other options...
You can see your own deleted recent questions (recent questions that were deleted; not recently deleted questions) under the questions tab of your profile, just click the "deleted recent questions" link below the list of answers. So if the question was your own it may be there.
Similarly, you can see your deleted recent answers under the answers tab of your profile. You can only see these if you have the ability to see the question that they were posted to though.
Interestingly, according to Change the link to deleted recent answer in case the question has been deleted you can see the revision history of your answer even if you can't see the question (that doesn't help you much in seeing the question though).