I think a zombie picked up all of my items and did not drop them

i had just started mining and a zombie killed me. I spawned where my bed was, and used no more than 1 minute to get down to where i died. The zombie was still there with my diamond helmet, but everytning else was missing. I dont think my items despawned because i didn't use 5 minutes to get down there. Is this a bug and can it be fixed?