Well I'm not sure what grade level your in, so I'm going to do my best to edit/comment on this as if it were an English Comp 2 college level poem. Before i start, it should be said that poems are easily my weakest area of writing. That said, I still consider myself capable.
Bottled up inside of me,
Deep within my heart,
The agony I've hidden,
Feelings I've denied.
All these
words things I've kept inside,
Words I've been too scared to say. --
Possibly put "And" in front of words in this line - more cluttered but if its not there then it's up to the reader to assume that "and" is there - your preference. Bottled up inside of me,
My thoughts of us,
All the ones I haven't shared,
I feel
as I should say something,
To express to you how I feel.
But when I
go try to say the words,
My
tongue twists into knots. (You spelled tongue wrong, I corrected it here)
Bottled up inside of me,
Thoughts
and feelings I can't let out.
So I'm stuck, This is too short for a line here, doesn't flow at all. Writing down my thoughts,
Writing down this poem. -
I don't really like these last lines - it might work if they were the last lines simply because its a way to end a poem, however you have another ending following. My English professor always harped about now having two endings to a poem like that.Bottled up inside of me,
My love to you.
This line is too short, revise it. Something like "The love i feel for you". Basically you want to end the poem on something that flows, going from a line with 6 syllables to one with 4 does not. If this was my comp 2 class, it would prolly be around a high D or C; at the Sophomore or JR level of High school, I'd expect at least a B from it.