I use the common ratio of 1:100, so if a Smurf is 150 years old, then they are biologically about 15 in human terms.
Of course the internet is unfair. It's just like the real world; you need to grow a thick skin and not let the little things bother you or else you will die. That's life.
You also need to ask permission and give proper credit to the artist whose sketch you used on your user page to make the colored OC picture (which is me, and it was my old Sony-styled Moxette sketch from nearly a decade ago).
In the top right corner of your pages, you should be able to see three vertical dots (like what is here on the comments section at the right of each reply), and in that dropdown menu to follow, you should see an option for "Protect." If not, then it may be an administrator feature, so just let the admins know (I would include myself, but I know that Vic and AHS are more frequently present these days whereas I tend to pop in and out).
If you have not done so already, I recommend protecting your pages so that only registered users can edit them. This prevents random people without logins from trolling your pages.