If you are translating line by line without any regard to other sentences, your translation is okay.  However, if taken as a whole, you needed extra words here and there to give the English a better polish.  Every line in a poem must begin with a capital letter.  Also punctuation is very important in English.

I miss you

I don't know who you are you
我不知道你是谁
Or where you are you from
来自哪里
Suddenly, you burst into my life
你突然闯入我的生活
And then touched my heart.
触动了我的信玄 What does this mean?
You were smiling to me in my dream...
梦里你在对我微笑
sunshine was very warm The sunlight is so warm.
阳光如此温暖
Your smile was so sweet!
你的微笑如此甜蜜
I will/shall never forget it
我将永远无法忘记
it's branded Memories deeply etched in my heart [branded is the correct translation but in English we don't express like this]

它被深深地烙印在我的心里

Once you said told that you loved me
你说过你爱我
you would will waite for me forever
你会永远等我
but I have never responded to your love [I prefer, "Your love was never reciprocated"]
但我从未回应过你的爱
One day,
一天
You left me
你离开了我
And nothing was left...
什么也没留下
Only your there three photographs
只有三张你的照片
and the beautiful memorise memories.
和那美好的回忆

You are a gust of the breeze.
你是一阵微风
Came and gone went in haste
来去匆匆
gently touched grazing gently on my face and my heart [I prefer "... and piercing my heart" but then it won't be an accurate translation.]
轻抚着我的脸颊和内心
and kissing my eyes.
亲吻着我的双眼

I don't know where are you are
我不知道你在哪里
nor what are you are doing.
在做什么
The only one thing I know
我只知道一件事
Is that I miss you.
我想你
if, you come back because of for me, you came back...
如果你为了我而回来
This time -  
这一次
I will hold grab hold of you and never let you go.
我会抓住你，永远不让你离开