More than 6,000 days studying (for study) English

Someone asked me how long I had (have) been studying English.
"For 17 years",I replied.
Then I realized that I had spent more than 6,000 days studying (for study) this language.

I started to study (studied) English when I was 10 years old.
It was a required subject, so I needed to attend English class.
Nowadays, most (of) Thai students start to study English when they are 5 years old.

At the (In that) time, I hated English.
I thought that I would never be able to understand this language.
But thanks MTV, P!nk brought me to the English world, eventually.

Did I really study English?
Did I really spend (spent) more than 6,000 days LEARNING it?

I think I just "attended in English classes" and got A B C or D instead of language skills.
(In fact, I've never got C or D in English classes even my grammar is very bad haha )

Well, I think I need to start my (the) first day of really learning English. (my actual English learning.)