Usually "junior" is ranked according to some measure of experience (years in the job) and skill level (what you can do). Self taught isn't a problem so long as you can actually do things.
Each company will rank a little differently. A junior dev in one company might be a developer in another. It depends what they are looking for. An applicant might have the core programming skills but not have experience in automated testing, for example.
You can always apply for a mid-range job and if they turn you down, ask for feedback on what they were looking for that you didn't have. Some places will offer a lower role if they like you but don't think you've got the full skills for what you came in for, too.
So... apply and have an honest conversation about what you are looking for and why; and what you have experience doing.