signs you're getting old

On Google Chat today...
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me: oh well anyway, i dont' feel so good.  i need to rest up for (insert work complaint here). 
SMH
Paul: smh?
me: ha! i'm not the only one who doesn't know that abbreviation! guess what it means!
Paul: shoot me in the head.  i dont know
me: CLOSE! shake my head
Paul: what?
me: i thought it was "so much hate." hahahahaha
Paul: what is it
me: SHAKE MY HEAD!  SMH
Paul: thats stupid
ts
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So I just learned what SMH meant yesterday.  This whole time, I thought it meant "so much hate" because it's on almost every single angry status update on Facebook.  It made sense to me.  I forgot that these abbreviations are usually some sort of action, like LOL or ROFL.  Geez, and I thought I was hip and happening.  And so it begins...glad I'm not alone.

PS.  I love how he added his own abbreviation at the end! LOL!
PPS.  Now that I think of it, is it shake my head or shakes my head?  so much hate...