Sure enough, those two posts were made by different IP addresses from what you usually appear to post from (checking your post history into 2013, at the very least).
There does seem to be another MotK person possibly in the same range who also posted in the 14.5 thread, but the posting style is different. In fact, the IP address for #2 in Ammy's post there and
this post are identical! Therefore, it appears that Psyduckxoxo may be responsible for this.
#1 doesn't match up with anyone else, it seems,
That's just what the facts show, here. Do you have any thoughts on who this is?
Also, change your password so this doesn't happen again.