I've completed an essay this year at uni and now that it has been submitted i've realised that I have previously completed a paper with a similar theme. the essay is making a different argument however it uses 2 of the same case studies (completely coincidental as they are the most promiment examples) and sets out some of the same facts in order to make the argument. It also discusses the same political doctrine (although to make different points). Through presenting facts in the same case studies i'm worried that i have unintentially self-plagarised myself and i'm unsure on what to do about it. Turnitin states that there is 0% similarilty and none of the citations in the two essays are the same hwoever i'm scared that the fact some of the case studies, and refer to the same doctrine, constitutes self-plagiarism?
Just wanted some opinions on whether this is self-plaiarism and whether I should bring it to the attention of my professor, or whether this would be seen as an admission of guilt. I would never cheat and i'm scared that it is going to look like I have, despite the fact I never looked at the previous essay while writing the new paper.
I would be grateful for any advice! I've been suffering from bad anxiety for a while now this has just made it worse and I cannot get it off my mind. Thanks in advance for the help.