It's like asking, is it too young for a 12 yr old to wear a sanitary pad? Heck, if she has a period, she should wear it.
If you have nipples showing through clothes and drawing extra, unwanted, embarrassing looks from guys, then yes, it's necessary.
I don't know of any covers, other than nursing pads to catch milk drips. I may be wrong but I've not heard of nipple covers. So ask your Mom. Tell her why you want better coverage. She was once your age, so she should be able to understand that awkward transitional age. I'm in my 50s and still remember mine. My mom said it didn't look like I was showing. I told I still felt uncomfortable and that's why I hunched my shoulders. She allowed me to get my first bra. I was still girls undershirts at that point. [ Dragonflymagic's advice column | Ask Dragonflymagic A Question ]
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