Hi mick, welcome!!! You got through it despite depression and everything else you got through it - that's no small victory. What Christine said was right your reaction post op was likely medication related! No need to be embarrassed - I used to be a nurse and believe me we've - they've seen it ALL!
in fact here was a recent thread here by dejeer - he's a survivor - his wife was in the hospital and had a wicked reaction (delusions paranoia etc..) to something... Not funny at the time but in retrospect - it is what it is!! Good luck. Read around - give some input everyone's voice is valuable... Take care!