I had a perma puppy applier in my inventory that I got for free from the MM and now it's gone from my inventory. I have never used it so I was wondering if it was possible I sold it by accident?
You created a thread to sell one around two hours ago: here Sounds like you sold it off and forgot about it. If that trade didn't happen, then the only way to sell it apart from trading it is to put it on the FM (it shows under specialty items). This should be on a lower section in your inventory just above your trinkets if you do still have it.