yep.. but CharmedRaptor832 has also been taken... change your name into CharmedRaptor833
Should I change my username?

No. Unless you have a REALLY good reason and from previous posts, that seems unlikely. So, again, no.

Yes, but on the condition that you are only allowed to change it to gm_yoavjm_2004, which you are only allowed to do once you become a GM
Is this an evolution of "can this forum(sic) get 1000 comments"?
https://www.chess.com/forum/view/general/please-do-not-question-why-i-am-doing-this-trend
Yes, you should