I understand what you mean, I've felt like that a few times myself. When I first started wanting to write up my story ideas, I realised my writing skills weren't great, and I felt really disheartened. I kept thinking to myself 'how can I be a writer when I can't write?' But I carried on writing anyway, simply because I love creating characters and their stories. Even if you're not like other writers (or in my case, can't write as well as them!) it doesn't make you any less of a writer. If you keep on writing and love what you're doing, it's simple, you are a writer.