Newbie to cover letters; the 4 I sent didn't have the names or addresses of the company on them but were good. Am I screwed for those jobs?

Alright so I sort of skimmed how to write a cover letter because it's boring and I hate it. Basically, instead of writing the name/address of the company I fucked up and wrote my own name/address at the top. I addressed the company in the "Dear _______ Hiring Managers" part. And then had really great, personal cover letters otherwise.

I have fixed this now but I feel dumb for the ones that I sent out. I have a solid resume, it's just that none of the jobs that I had ever required cover letters.

Do you think that this mistake ruins my chance at those jobs? (They were for jobs at online publications and internships at entertainment companies).

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