Is it cruel or funny to embarr your adult son on the dancefloor?

I saw my 20yr old son in the same nightclub as me, with his friends and a girl he was trying to impress. The devil overtook me, I'm afraid, and I went to the dancefloor and greeted him effusively with a cry of 'come on son, lets get funky' and proceeded to boogy on down with them for a short while. His friends loved it, but he tried to get the dancefloor to swallow him up. Was I cruel or was it funny? (I am a 'hot mum' by the way!!!