Simple water drop for use as needed… Multiple drops can add to the effect.

Open an image of a leaf or whatever you want.

Create a new Layer 1 then proceed to draw an ellipse using the ellipse tool.

Using the Gradient tool with foreground to black and the background color to white.

Drag the cursor for the gradient tool from one side of the ellipse to the other to create something like this.

Next change Layer 1 blend mode to Overlay.

Within the Blending Options – Drop Shadow Dialogue copy similar settings (you can experiment) then apply it.

Again, in the Blending Options dialogue box add Inner Shadow with similar settings then apply.

Now we need to add the shine effect.
To keep the shiny dot separate from the rest of the image, create a new layer 2.
Use the brush tool with a small soft diameter to make a dot (experiment).

After these simple steps, this is what you end up with. You can make multiple water drops to heighten the effect. Remember that you can experiment with these settings to make it look the way you want.

Good Luck! I used a four leaf clover for this example to bestow upon you my best wishes and luck in creating this water drop.