stumblejohn 

An exclamation used to show anger.

Stumblejohn! I can't beleive I wen't and did that without thinking...

stumblejohn by Kirby Peawauket May 3, 2005

Stumblejoy 

To come unexpectedly or by chance upon something pleasurable; unexpected pleasure; pleasantly surprised.

“When we booked our stay at the hotel, we had no idea our favorite band would be playing a gig there. Pure stumblejoy.”

Stumblejoy by SalvyZ May 19, 2019