I'm not into makeup. The most I wear is lipgloss and occasionally mascara. However I put on some pencil eyeliner for fun recently (my mom wears it every day and has been wearing it since she was a teen) and liked the look of it.
I say do what you want to do. i experimented with wearing eyeliner when i was in the 4th/5th grade. it was of course badly done, but it was what i wanted to do. i stopped wearing makeup by the sixth grade aside from a bit of lip gloss here or there, or playing around with lipsticks and eye-shadows at home. i then started to really wear makeup (eye-makeup) when i went into high school. again i wasn't great at makeup but practice makes perfect and it was what i wanted to do. now that I've been out of high school for a while i am great at makeup and im comfortable without it too. i never put a restriction on anything because it was me, it was self expression and it made me happy.
How much or how you do it depends on how you think looks best on you. And what you feel happiest with. Don't do an x amount just because others told you to. It's your own decision. Same goes for when you start. It's up to you to decide because it's YOUR body.
To each is her own, but I didn't start wearing eyeliner or even experimenting with make-up until I was 18. My mom wouldn't let us wear make-up and while back in the day it used to irritate me, now that I'm a grown adult I totally understand why and I'm happy she enforced that decision. Not wearing make-up until I was an adult kept me humble and forced me to apply my true self instead of hiding behind some pretty art on my face. Like you, all I wore was lip gloss.
At what age do I think it's okay to begin wearing eyeliner? I guess it depends on the female and he reasoning for doing it. I do feel like it's better to wait because the self-esteem is so fragile at a certain age period that it becomes effortless for girls to use make-up to compensate for other insecurities. It can definitely look like someone is trying too hard especially if their make-up is on point but their personality could noticeably use some work.
I'm 16 and I've been wearing it since i was probably 13. Your eyeliner looks nice, I think it makes your eyes seem bigger and draws attention, that's why i wear it :) don't be afraid to try out new makeup if you want to. I tend to wear it quite thick with those cat flicks on the end :)
All i wear is eyeliner and mascara period , Use it and mascara nothing more , its a simple look , and ur features would stay , just dont use other than that , and i started at age 15 -16 , now im 20