This is beautiful. I love haikus... how simple they look, but how hard they are to write. I love how you intensify this image, a seemingly insignificant, but totally real "small death." Good job!

I assume you are familiar with the double-entendre here?  (That is, "la petite mort," or "the little death," is a common literary metaphor for orgasm.)

The poem is even better under that consideration -- I love something that works equally well on two levels.  "Drown[ing] in sweetness" is a beautiful description both of a literal flower dipping into a pond and of an orgasm; the first two lines are darling on a literal level (a flower kissing the pond), and evocative on a sexual level (it's a pretty obvious penetrative metaphor: the stiff, phallic flower bending to enter the wet, receptive pool). 

I'm not sure what to make of the "limp" flower, though... that seems odd in the metaphorical context.  Perhaps I'm misreading masculinity into here: the limp flower could easily be a tongue or a finger, male or female.  Or perhaps you're playing with my assumptions here, and the "limp flower" is intentionally blurring the boundaries between potent and impotent.

Or maybe I've completely misread the poem and you only intended the literal level... but I hope not, because it works so well.

This kind of reminds me of the Greek myth of Narcissus, where he sees his reflection and becomes so absorbed in his own beauty that he can't stop looking at himself and eventually turns into a beautiful flower, which still leans towards the water. Possibly not the intentional parallel -- but intentional or otherwise, I really liked it.

I don't usually really like haiku, as I feel like restricting oneself to something so short with such a restrictive meter usually manages to destroy what could have been said in a longer poem. However, I love the simplicity of this, and the way you use the meter to your advantage, and don't make it seem forced.

Excellent job -- keep writing! 

Very nice! Kind of sad, but with good figurative language and imagery.