If you decide you want to change your social media profile names, you can do so.
For example, Facebook, Twitter and Instagram will have functionalities that will enable you to change your names.
Please note that sometimes, the new name may get rejected if the name is completely different from what you are changing from.
For example, changing from PaulOMahony to Tesco will be considered a major difference.
However, going from PaulOMahony to PaulOMahonySpeaker will be easier to be approved.
Also, remember, that name needs to be available and not be occupied by someone else.
Please find instructions on how to change names below:
Facebook Page: https://www.facebook.com/help/271607792873806
Instagram: https://help.instagram.com/583107688369069
Twitter: https://help.twitter.com/en/managing-your-account/change-twitter-handle
Blogger: http://blogger-tutorialss.blogspot.com/2013/08/Change-your-Blog-Name-in-Blogger.html