And no, it's different to a hallucination, as a confabulation can only be retrospective (hallucinations are happening at the time)
"But i swear that time in year 8 the teacher was wearing huge come fuck me boots to class..."
Bob: "oh yeah. i loved the part where... WTF?! OMFG! u beyotch! coffee! WTH?...yup, that was good stuff"
Kayli: "oh don't mind bob, he's just suffering from confabulation. poor guy"