Getting the dof right in macros always escaped me, the stamens and the rear petal are spot on but too much of the foreground is blurred for my taste. The exposure is spot, lots of detail in that white petal.

Its awesome how you managed to capture the slight yellow reflection/pollon circle on the petals!
Great Job

Stunning capture.

Your focus point should have been locked at about a third of the way from the left border, on the leading edge of the LEFT petal.
Even if your lens opening was too wide, as is common with Trilliums'( they are usually in deep shade), the prime focus would cover everything in that plan, including the stamens, and even a shallow depth of field would have retained much more detail.
Check you camera manual on how to lock focus on a specific point, and still be able to recompose the image to your liking.
Also, breaking the border with all three petals may have retained a sense of compositional balance but it's not really aesthetically pleasing. Generally, exiting a border with any part of the prime subject is rarely acceptable unless the composition is extremely powerful and it adds to the impact.
That said, it's a fine perspective and with very minor corrections would be excellent.

Truly beautyfull

I have to agree with snapshooter. Actually his advise applys to me also. In my interpretation, I find the image a little overexposed and slightly out of focus. Still a nice composition and a difficult shot for a closeup.