It's alright. I do think the actual issue was worded perhaps a bit harshly and combative, and I think you responded correctly. Very much appreciate the accountability here. To be honest if anything, this probably gives me more faith in you in the long run. There are many ways you could have dealt with it, but as far as I can see you've dealt with the issue as honorably as you could have.
Proper attribution can be tricky. We all learn. We all make mistakes. A lot of us will never release a project that makes it as far as yours has so even our issues don't become even nearly as visible.
Keep your head up and stay calm. You're doing great. We got you.