what’s the difference between glückwunch and glücklich?

aw Tito & Tarantula last night…they closed with a triple speed version of La Bamba…I think the song was about 30 seconds long…they broke for an accapella aaaahhh…ahhhhhhhhhhh……ahhhhhhhhhhhh….ahhhh…then repeated the same 30 second song….t’was cool….