I understood your poem the minute I saw it was an "acrostic". Yes, your poem did have a hidden message and the reason the others may have missed it is because they were not "expecting" you to know what you were doing because it didn't "seem" like you constructed it correctly (the stanza breaks looked out of place). What they "should" have done was to give you the benefit of the doubt and tried to see "why" the stanzas weren't as you'd expect...if they "had", they'd have seen the "I love you" of the acrostic and understood the hidden meaning.
That being said, you have a couple hard spots in the poem itself. For example, "why" is lonliness and time of the essence? You say that "until that day I be waiting for you then" (which is another line you "really" need to revise), so what's the hurry? In other words, you need to make sure there is agreement between your concepts and lines.
So you know, this poem didn't have to rhyme. You could have done this as free verse and probably expressed your feelings more accurately. However, since you tried to do a rhymed poem, let's continue...
"Vunerable"? did you mean "vulnerable"? and if you did, why were you "Vulerable" to do everything right? You see, it's important to not only pick a word that starts with the right letter, you need to make sure it "belongs" in the line on its own merit. I'm not sure Vulnerable does.
I'd also change "the hidden feeling from within" to "the hidden message I penned within".
"until that day..." I told you'd we be back here. "I be waiting"??? no way. I've thought about another way to say this with "then" and I'm drawing a blank. Maybe you should chage the preceeding line so it can end with a different word? I'm not sure, but this one just doesn't work (and it's not even proper English).
So, I'd give you a 6 out of 10 for the poem, because in spite of the poetic errors, you did a decent job at an acrostic...one which in spite of giving clues to the readers, most of them missed. (their fault, not yours).
Just so you know, another way to draw attention to the "secret" message in an acrostic is to build your stanzas so they sound like they belong together...then the reader wonders why there are different number of lines with each stanza and it draws them in. However, "your" method should have worked...maybe the last line cost you some credibility, I'm not sure.
In any event, nice job...edit and keep writing!